<?xml version="1.0" encoding="us-ascii"?>
<!--XBRL document created with Toppan Merrill Bridge  9.4.0.81 -->
<!--Based on XBRL 2.1-->
<!--Created on: 11/13/2019 4:00:55 PM-->
<!--Modified on: 11/13/2019 4:00:55 PM-->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xlink="http://www.w3.org/1999/xlink">
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DocumentDocumentAndEntityInformation" roleURI="http://www.ymabs.com/role/DocumentDocumentAndEntityInformation" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#StatementConsolidatedBalanceSheets" roleURI="http://www.ymabs.com/role/StatementConsolidatedBalanceSheets" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#StatementConsolidatedBalanceSheetsParenthetical" roleURI="http://www.ymabs.com/role/StatementConsolidatedBalanceSheetsParenthetical" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#StatementConsolidatedStatementsOfNetLossAndComprehensiveLoss" roleURI="http://www.ymabs.com/role/StatementConsolidatedStatementsOfNetLossAndComprehensiveLoss" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#StatementConsolidatedStatementsOfChangesInStockholdersEquity" roleURI="http://www.ymabs.com/role/StatementConsolidatedStatementsOfChangesInStockholdersEquity" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#StatementConsolidatedStatementsOfCashFlows" roleURI="http://www.ymabs.com/role/StatementConsolidatedStatementsOfCashFlows" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureOrganizationAndDescriptionOfBusiness" roleURI="http://www.ymabs.com/role/DisclosureOrganizationAndDescriptionOfBusiness" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureBasisOfPresentation" roleURI="http://www.ymabs.com/role/DisclosureBasisOfPresentation" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureSummaryOfSignificantAccountingPolicies" roleURI="http://www.ymabs.com/role/DisclosureSummaryOfSignificantAccountingPolicies" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureNetLossPerShare" roleURI="http://www.ymabs.com/role/DisclosureNetLossPerShare" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureAccruedLiabilities" roleURI="http://www.ymabs.com/role/DisclosureAccruedLiabilities" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitments" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitments" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureStockholdersEquity" roleURI="http://www.ymabs.com/role/DisclosureStockholdersEquity" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureShareBasedCompensation" roleURI="http://www.ymabs.com/role/DisclosureShareBasedCompensation" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureRelatedPartyTransactions" roleURI="http://www.ymabs.com/role/DisclosureRelatedPartyTransactions" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureIncomeTaxes" roleURI="http://www.ymabs.com/role/DisclosureIncomeTaxes" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureOtherBenefits" roleURI="http://www.ymabs.com/role/DisclosureOtherBenefits" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureSubsequentEvents" roleURI="http://www.ymabs.com/role/DisclosureSubsequentEvents" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureSummaryOfSignificantAccountingPoliciesPolicies" roleURI="http://www.ymabs.com/role/DisclosureSummaryOfSignificantAccountingPoliciesPolicies" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureNetLossPerShareTables" roleURI="http://www.ymabs.com/role/DisclosureNetLossPerShareTables" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureAccruedLiabilitiesTables" roleURI="http://www.ymabs.com/role/DisclosureAccruedLiabilitiesTables" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitmentsTables" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsTables" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureShareBasedCompensationTables" roleURI="http://www.ymabs.com/role/DisclosureShareBasedCompensationTables" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureOrganizationAndDescriptionOfBusinessDetails" roleURI="http://www.ymabs.com/role/DisclosureOrganizationAndDescriptionOfBusinessDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureBasisOfPresentationDetails" roleURI="http://www.ymabs.com/role/DisclosureBasisOfPresentationDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureSummaryOfSignificantAccountingPoliciesLeasesAndSegmentsDetails" roleURI="http://www.ymabs.com/role/DisclosureSummaryOfSignificantAccountingPoliciesLeasesAndSegmentsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureSummaryOfSignificantAccountingPoliciesRecentlyIssuedAccountingPronouncementsDetails" roleURI="http://www.ymabs.com/role/DisclosureSummaryOfSignificantAccountingPoliciesRecentlyIssuedAccountingPronouncementsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureNetLossPerShareBasicAndDilutedDetails" roleURI="http://www.ymabs.com/role/DisclosureNetLossPerShareBasicAndDilutedDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureNetLossPerShareAntiDilutiveSecuritiesDetails" roleURI="http://www.ymabs.com/role/DisclosureNetLossPerShareAntiDilutiveSecuritiesDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureAccruedLiabilitiesDetails" roleURI="http://www.ymabs.com/role/DisclosureAccruedLiabilitiesDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitmentsDetails" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitmentsMskLicenseAgreementDetails" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsMskLicenseAgreementDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitmentsCd33LicenseAgreementDetails" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsCd33LicenseAgreementDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitmentsMabvaxSublicenseAgreementDetails" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsMabvaxSublicenseAgreementDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitmentsOtherAgreementsDetails" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsOtherAgreementsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitmentsLeaseAgreementsDetails" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsLeaseAgreementsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitmentsLeaseCostsDetails" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsLeaseCostsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitmentsLeaseMaturitiesDetails" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsLeaseMaturitiesDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitments2018LeaseMaturitiesDetails" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitments2018LeaseMaturitiesDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureLicenseAgreementsAndCommitmentsLeaseTermAndDiscountRateDetails" roleURI="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsLeaseTermAndDiscountRateDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureStockholdersEquityAuthorizedCommonAndPreferredStockDetails" roleURI="http://www.ymabs.com/role/DisclosureStockholdersEquityAuthorizedCommonAndPreferredStockDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureStockholdersEquityStockGrantAgreementsWithNonEmployeesStockDetails" roleURI="http://www.ymabs.com/role/DisclosureStockholdersEquityStockGrantAgreementsWithNonEmployeesStockDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureStockholdersEquityStockGrantAgreementsWithNonEmployeesStockOptionsDetails" roleURI="http://www.ymabs.com/role/DisclosureStockholdersEquityStockGrantAgreementsWithNonEmployeesStockOptionsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureStockholdersEquityIssuanceOfCommonStockIpoDetails" roleURI="http://www.ymabs.com/role/DisclosureStockholdersEquityIssuanceOfCommonStockIpoDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureStockholdersEquityIssuanceOfCommonStockStockGrantAgreementsDetails" roleURI="http://www.ymabs.com/role/DisclosureStockholdersEquityIssuanceOfCommonStockStockGrantAgreementsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureShareBasedCompensation2015PlanDetails" roleURI="http://www.ymabs.com/role/DisclosureShareBasedCompensation2015PlanDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureShareBasedCompensation2018PlanDetails" roleURI="http://www.ymabs.com/role/DisclosureShareBasedCompensation2018PlanDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureShareBasedCompensationExpenseDetails" roleURI="http://www.ymabs.com/role/DisclosureShareBasedCompensationExpenseDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureShareBasedCompensationStockOptionsDetails" roleURI="http://www.ymabs.com/role/DisclosureShareBasedCompensationStockOptionsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureShareBasedCompensationUnrecognizedCompensationDetails" roleURI="http://www.ymabs.com/role/DisclosureShareBasedCompensationUnrecognizedCompensationDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureShareBasedCompensationRestrictedStockUnitActivityDetails" roleURI="http://www.ymabs.com/role/DisclosureShareBasedCompensationRestrictedStockUnitActivityDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureRelatedPartyTransactionsDetails" roleURI="http://www.ymabs.com/role/DisclosureRelatedPartyTransactionsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureIncomeTaxesExpenseDetails" roleURI="http://www.ymabs.com/role/DisclosureIncomeTaxesExpenseDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureIncomeTaxesUncertainTaxPositionsDetails" roleURI="http://www.ymabs.com/role/DisclosureIncomeTaxesUncertainTaxPositionsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureOtherBenefitsDetails" roleURI="http://www.ymabs.com/role/DisclosureOtherBenefitsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="ymab-20190930.xsd#DisclosureSubsequentEventsDetails" roleURI="http://www.ymabs.com/role/DisclosureSubsequentEventsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <presentationLink xlink:role="http://www.ymabs.com/role/DocumentDocumentAndEntityInformation" xlink:type="extended" xlink:title="00090 - Document - Document and Entity Information" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_DocumentAndEntityInformationAbstract" xlink:label="ymab_DocumentAndEntityInformationAbstract" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_DocumentType" xlink:label="dei_DocumentType_637092576538276567" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_DocumentType_637092576538276567" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_DocumentPeriodEndDate" xlink:label="dei_DocumentPeriodEndDate_637092576538296610" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_DocumentPeriodEndDate_637092576538296610" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityRegistrantName" xlink:label="dei_EntityRegistrantName_637092576538296610" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_EntityRegistrantName_637092576538296610" order="3" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityCurrentReportingStatus" xlink:label="dei_EntityCurrentReportingStatus_637092576538296610" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_EntityCurrentReportingStatus_637092576538296610" order="4" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityInteractiveDataCurrent" xlink:label="dei_EntityInteractiveDataCurrent_637092576538296610" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_EntityInteractiveDataCurrent_637092576538296610" order="5" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityFilerCategory" xlink:label="dei_EntityFilerCategory_637092576538296610" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_EntityFilerCategory_637092576538296610" order="6" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntitySmallBusiness" xlink:label="dei_EntitySmallBusiness_637092576538306635" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_EntitySmallBusiness_637092576538306635" order="7" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityEmergingGrowthCompany" xlink:label="dei_EntityEmergingGrowthCompany_637092576538306635" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_EntityEmergingGrowthCompany_637092576538306635" order="8" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityExTransitionPeriod" xlink:label="dei_EntityExTransitionPeriod_637092576538306635" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_EntityExTransitionPeriod_637092576538306635" order="9" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityShellCompany" xlink:label="dei_EntityShellCompany_637092576538306635" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_EntityShellCompany_637092576538306635" order="10" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityCommonStockSharesOutstanding" xlink:label="dei_EntityCommonStockSharesOutstanding_637092576538306635" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_EntityCommonStockSharesOutstanding_637092576538306635" order="11" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityCentralIndexKey" xlink:label="dei_EntityCentralIndexKey_637092576538326695" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_EntityCentralIndexKey_637092576538326695" order="12" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_CurrentFiscalYearEndDate" xlink:label="dei_CurrentFiscalYearEndDate_637092576538326695" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_CurrentFiscalYearEndDate_637092576538326695" order="13" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_DocumentFiscalYearFocus" xlink:label="dei_DocumentFiscalYearFocus_637092576538326695" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_DocumentFiscalYearFocus_637092576538326695" order="14" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_DocumentFiscalPeriodFocus" xlink:label="dei_DocumentFiscalPeriodFocus_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_DocumentFiscalPeriodFocus_637092576538336713" order="15" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_AmendmentFlag" xlink:label="dei_AmendmentFlag_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_DocumentAndEntityInformationAbstract" xlink:to="dei_AmendmentFlag_637092576538336713" order="16" use="optional" priority="2" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/StatementConsolidatedBalanceSheets" xlink:type="extended" xlink:title="00100 - Statement - Consolidated Balance Sheets" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_636747661984584916" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssetsAbstract" xlink:label="us-gaap_AssetsAbstract_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfFinancialPositionAbstract_636747661984584916" xlink:to="us-gaap_AssetsAbstract_637092576538336713" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="us-gaap_AssetsCurrentAbstract_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AssetsAbstract_637092576538336713" xlink:to="us-gaap_AssetsCurrentAbstract_637092576538336713" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AssetsCurrentAbstract_637092576538336713" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_637092576538336713" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestrictedCashCurrent" xlink:label="us-gaap_RestrictedCashCurrent_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AssetsCurrentAbstract_637092576538336713" xlink:to="us-gaap_RestrictedCashCurrent_637092576538336713" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherAssetsCurrent" xlink:label="us-gaap_OtherAssetsCurrent_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AssetsCurrentAbstract_637092576538336713" xlink:to="us-gaap_OtherAssetsCurrent_637092576538336713" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="us-gaap_AssetsCurrent_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AssetsCurrentAbstract_637092576538336713" xlink:to="us-gaap_AssetsCurrent_637092576538336713" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AssetsAbstract_637092576538336713" xlink:to="us-gaap_PropertyPlantAndEquipmentNet_637092576538336713" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AssetsAbstract_637092576538336713" xlink:to="us-gaap_OperatingLeaseRightOfUseAsset_637092576538336713" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="us-gaap_OtherAssetsNoncurrent_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AssetsAbstract_637092576538336713" xlink:to="us-gaap_OtherAssetsNoncurrent_637092576538336713" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Assets" xlink:label="us-gaap_Assets_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AssetsAbstract_637092576538336713" xlink:to="us-gaap_Assets_637092576538336713" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfFinancialPositionAbstract_636747661984584916" xlink:to="us-gaap_LiabilitiesAndStockholdersEquityAbstract_637092576538336713" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="us-gaap_LiabilitiesCurrentAbstract_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract_637092576538336713" xlink:to="us-gaap_LiabilitiesCurrentAbstract_637092576538336713" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:label="us-gaap_AccountsPayableCurrent_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LiabilitiesCurrentAbstract_637092576538336713" xlink:to="us-gaap_AccountsPayableCurrent_637092576538336713" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="us-gaap_AccruedLiabilitiesCurrent_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LiabilitiesCurrentAbstract_637092576538336713" xlink:to="us-gaap_AccruedLiabilitiesCurrent_637092576538336713" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_637092576538336713" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LiabilitiesCurrentAbstract_637092576538336713" xlink:to="us-gaap_OperatingLeaseLiabilityCurrent_637092576538336713" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="us-gaap_LiabilitiesCurrent_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LiabilitiesCurrentAbstract_637092576538336713" xlink:to="us-gaap_LiabilitiesCurrent_637092576538346734" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedMilestoneAndRoyaltyPaymentsNoncurrent" xlink:label="ymab_AccruedMilestoneAndRoyaltyPaymentsNoncurrent_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract_637092576538336713" xlink:to="ymab_AccruedMilestoneAndRoyaltyPaymentsNoncurrent_637092576538346734" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract_637092576538336713" xlink:to="us-gaap_OperatingLeaseLiabilityNoncurrent_637092576538346734" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract_637092576538336713" xlink:to="us-gaap_OtherLiabilitiesNoncurrent_637092576538346734" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Liabilities" xlink:label="us-gaap_Liabilities_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract_637092576538336713" xlink:to="us-gaap_Liabilities_637092576538346734" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="us-gaap_CommitmentsAndContingencies_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract_637092576538336713" xlink:to="us-gaap_CommitmentsAndContingencies_637092576538346734" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="us-gaap_StockholdersEquityAbstract_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract_637092576538336713" xlink:to="us-gaap_StockholdersEquityAbstract_637092576538346734" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PreferredStockValue" xlink:label="us-gaap_PreferredStockValue_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StockholdersEquityAbstract_637092576538346734" xlink:to="us-gaap_PreferredStockValue_637092576538346734" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockValue" xlink:label="us-gaap_CommonStockValue_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StockholdersEquityAbstract_637092576538346734" xlink:to="us-gaap_CommonStockValue_637092576538346734" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="us-gaap_AdditionalPaidInCapital_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StockholdersEquityAbstract_637092576538346734" xlink:to="us-gaap_AdditionalPaidInCapital_637092576538346734" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StockholdersEquityAbstract_637092576538346734" xlink:to="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_637092576538346734" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_637092576538346734" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StockholdersEquityAbstract_637092576538346734" xlink:to="us-gaap_RetainedEarningsAccumulatedDeficit_637092576538346734" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="us-gaap_StockholdersEquity_637092576538356759" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StockholdersEquityAbstract_637092576538346734" xlink:to="us-gaap_StockholdersEquity_637092576538356759" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_637092576538356759" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StockholdersEquityAbstract_637092576538346734" xlink:to="us-gaap_LiabilitiesAndStockholdersEquity_637092576538356759" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/StatementConsolidatedBalanceSheetsParenthetical" xlink:type="extended" xlink:title="00105 - Statement - Consolidated Balance Sheets (parenthetical)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="us-gaap_StatementOfFinancialPositionAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_637092576538366787" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfFinancialPositionAbstract" xlink:to="us-gaap_PreferredStockParOrStatedValuePerShare_637092576538366787" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="us-gaap_PreferredStockSharesAuthorized_637092576538366787" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfFinancialPositionAbstract" xlink:to="us-gaap_PreferredStockSharesAuthorized_637092576538366787" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PreferredStockSharesIssued" xlink:label="us-gaap_PreferredStockSharesIssued_637092576538366787" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfFinancialPositionAbstract" xlink:to="us-gaap_PreferredStockSharesIssued_637092576538366787" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_637092576538366787" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfFinancialPositionAbstract" xlink:to="us-gaap_CommonStockParOrStatedValuePerShare_637092576538366787" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="us-gaap_CommonStockSharesAuthorized_637092576538366787" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfFinancialPositionAbstract" xlink:to="us-gaap_CommonStockSharesAuthorized_637092576538366787" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockSharesIssued" xlink:label="us-gaap_CommonStockSharesIssued_637092576538366787" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfFinancialPositionAbstract" xlink:to="us-gaap_CommonStockSharesIssued_637092576538366787" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="us-gaap_CommonStockSharesOutstanding_637092576538376845" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfFinancialPositionAbstract" xlink:to="us-gaap_CommonStockSharesOutstanding_637092576538376845" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/StatementConsolidatedStatementsOfNetLossAndComprehensiveLoss" xlink:type="extended" xlink:title="00200 - Statement - Consolidated Statements of Net Loss and Comprehensive Loss" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:label="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingExpensesAbstract" xlink:label="us-gaap_OperatingExpensesAbstract_637092576538376845" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:to="us-gaap_OperatingExpensesAbstract_637092576538376845" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="us-gaap_ResearchAndDevelopmentExpense_637092576538376845" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingExpensesAbstract_637092576538376845" xlink:to="us-gaap_ResearchAndDevelopmentExpense_637092576538376845" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="us-gaap_GeneralAndAdministrativeExpense_637092576538376845" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingExpensesAbstract_637092576538376845" xlink:to="us-gaap_GeneralAndAdministrativeExpense_637092576538376845" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingExpenses" xlink:label="us-gaap_OperatingExpenses_637092576538376845" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingExpensesAbstract_637092576538376845" xlink:to="us-gaap_OperatingExpenses_637092576538376845" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="us-gaap_OperatingIncomeLoss_637092576538376845" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:to="us-gaap_OperatingIncomeLoss_637092576538376845" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:label="us-gaap_OtherNonoperatingIncomeExpenseAbstract_637092576538376845" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:to="us-gaap_OtherNonoperatingIncomeExpenseAbstract_637092576538376845" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_637092576538376845" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OtherNonoperatingIncomeExpenseAbstract_637092576538376845" xlink:to="us-gaap_OtherNonoperatingIncomeExpense_637092576538376845" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss_637092576538386859" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:to="us-gaap_NetIncomeLoss_637092576538386859" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="7" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_637092576538386859" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:to="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_637092576538386859" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent" xlink:label="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_637092576538386859" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_637092576538386859" xlink:to="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_637092576538386859" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_637092576538386859" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:to="us-gaap_ComprehensiveIncomeNetOfTax_637092576538386859" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarningsPerShareBasicAndDiluted" xlink:label="us-gaap_EarningsPerShareBasicAndDiluted_637092576538386859" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:to="us-gaap_EarningsPerShareBasicAndDiluted_637092576538386859" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:label="us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted_637092576538386859" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:to="us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted_637092576538386859" order="8" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/StatementConsolidatedStatementsOfChangesInStockholdersEquity" xlink:type="extended" xlink:title="00300 - Statement - Consolidated Statements of Changes in Stockholders' Equity" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementOfStockholdersEquityAbstract" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementTable" xlink:label="us-gaap_StatementTable_637092576538396880" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfStockholdersEquityAbstract" xlink:to="us-gaap_StatementTable_637092576538396880" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="us-gaap_StatementEquityComponentsAxis_637092576538396880" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementTable_637092576538396880" xlink:to="us-gaap_StatementEquityComponentsAxis_637092576538396880" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockMember" xlink:label="us-gaap_CommonStockMember_637092576538396880" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementEquityComponentsAxis_637092576538396880" xlink:to="us-gaap_CommonStockMember_637092576538396880" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="us-gaap_AdditionalPaidInCapitalMember_637092576538396880" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementEquityComponentsAxis_637092576538396880" xlink:to="us-gaap_AdditionalPaidInCapitalMember_637092576538396880" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_637092576538396880" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementEquityComponentsAxis_637092576538396880" xlink:to="us-gaap_AccumulatedOtherComprehensiveIncomeMember_637092576538396880" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="us-gaap_RetainedEarningsMember_637092576538396880" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementEquityComponentsAxis_637092576538396880" xlink:to="us-gaap_RetainedEarningsMember_637092576538396880" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="us-gaap_EquityComponentDomain_637092576538396880" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementEquityComponentsAxis_637092576538396880" xlink:to="us-gaap_EquityComponentDomain_637092576538396880" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementLineItems" xlink:label="us-gaap_StatementLineItems_637092576538396880" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementTable_637092576538396880" xlink:to="us-gaap_StatementLineItems_637092576538396880" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:label="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_637092576538396880" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementLineItems_637092576538396880" xlink:to="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_637092576538396880" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="us-gaap_StockholdersEquity_637092576538406898" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_637092576538396880" xlink:to="us-gaap_StockholdersEquity_637092576538406898" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="us-gaap_CommonStockSharesOutstanding_637092576538406898" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_637092576538396880" xlink:to="us-gaap_CommonStockSharesOutstanding_637092576538406898" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_637092576538406898" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_637092576538396880" xlink:to="us-gaap_StockIssuedDuringPeriodValueNewIssues_637092576538406898" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_637092576538406898" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StockIssuedDuringPeriodValueNewIssues_637092576538406898" xlink:to="us-gaap_StockIssuedDuringPeriodSharesNewIssues_637092576538406898" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueIssuedForServices" xlink:label="us-gaap_StockIssuedDuringPeriodValueIssuedForServices_637092576538406898" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_637092576538396880" xlink:to="us-gaap_StockIssuedDuringPeriodValueIssuedForServices_637092576538406898" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesIssuedForServices" xlink:label="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_637092576538406898" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StockIssuedDuringPeriodValueIssuedForServices_637092576538406898" xlink:to="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_637092576538406898" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition_637092576538406898" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_637092576538396880" xlink:to="us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition_637092576538406898" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_637092576538416922" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_637092576538396880" xlink:to="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_637092576538416922" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss_637092576538416922" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_637092576538396880" xlink:to="us-gaap_NetIncomeLoss_637092576538416922" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="us-gaap_StockholdersEquity_637092576538416922" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_637092576538396880" xlink:to="us-gaap_StockholdersEquity_637092576538416922" order="8" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="us-gaap_CommonStockSharesOutstanding_637092576538416922" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_637092576538396880" xlink:to="us-gaap_CommonStockSharesOutstanding_637092576538416922" order="9" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/StatementConsolidatedStatementsOfCashFlows" xlink:type="extended" xlink:title="00400 - Statement - Consolidated Statements of Cash Flows" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="us-gaap_StatementOfCashFlowsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_637092576538426951" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_637092576538426951" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProfitLoss" xlink:label="us-gaap_ProfitLoss_637092576538426951" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_637092576538426951" xlink:to="us-gaap_ProfitLoss_637092576538426951" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_637092576538426951" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_637092576538426951" xlink:to="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_637092576538426951" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="us-gaap_DepreciationDepletionAndAmortization_637092576538426951" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_637092576538426951" xlink:to="us-gaap_DepreciationDepletionAndAmortization_637092576538426951" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="us-gaap_ShareBasedCompensation_637092576538426951" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_637092576538426951" xlink:to="us-gaap_ShareBasedCompensation_637092576538426951" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ForeignCurrencyTransactionGainLossBeforeTax" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_637092576538426951" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_637092576538426951" xlink:to="us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_637092576538426951" order="3" use="optional" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_637092576538426951" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_637092576538426951" xlink:to="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_637092576538426951" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInOtherCurrentAssets" xlink:label="us-gaap_IncreaseDecreaseInOtherCurrentAssets_637092576538426951" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_637092576538426951" xlink:to="us-gaap_IncreaseDecreaseInOtherCurrentAssets_637092576538426951" order="1" use="optional" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="7" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentAssets" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_637092576538426951" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_637092576538426951" xlink:to="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_637092576538426951" order="2" use="optional" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="7" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayable" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_637092576538436976" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_637092576538426951" xlink:to="us-gaap_IncreaseDecreaseInAccountsPayable_637092576538436976" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_IncreaseDecreaseInAccruedLiabilitiesAndOther" xlink:label="ymab_IncreaseDecreaseInAccruedLiabilitiesAndOther_637092576538436976" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_637092576538426951" xlink:to="ymab_IncreaseDecreaseInAccruedLiabilitiesAndOther_637092576538436976" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_637092576538436976" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_637092576538426951" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivities_637092576538436976" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_637092576538436976" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_637092576538436976" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_637092576538436976" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_637092576538436976" xlink:to="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_637092576538436976" order="1" use="optional" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_637092576538436976" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_637092576538436976" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivities_637092576538436976" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_637092576538436976" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_637092576538436976" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_637092576538447008" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_637092576538436976" xlink:to="us-gaap_ProceedsFromIssuanceOfCommonStock_637092576538447008" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsOfStockIssuanceCosts" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_637092576538447008" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_637092576538436976" xlink:to="us-gaap_PaymentsOfStockIssuanceCosts_637092576538447008" order="2" use="optional" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" priority="8" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_637092576538447008" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_637092576538436976" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivities_637092576538447008" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_637092576538447008" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_637092576538447008" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_637092576538447008" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_637092576538447008" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_637092576538457033" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_637092576538457033" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_6370925765384570331" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_6370925765384570331" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:label="us-gaap_NoncashInvestingAndFinancingItemsAbstract_637092576538457033" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_NoncashInvestingAndFinancingItemsAbstract_637092576538457033" order="8" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CapitalExpendituresIncurredButNotYetPaid" xlink:label="us-gaap_CapitalExpendituresIncurredButNotYetPaid_637092576538457033" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncashInvestingAndFinancingItemsAbstract_637092576538457033" xlink:to="us-gaap_CapitalExpendituresIncurredButNotYetPaid_637092576538457033" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_637092576538457033" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncashInvestingAndFinancingItemsAbstract_637092576538457033" xlink:to="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_637092576538457033" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_NoncashOrPartialNoncashTransactionCommonStockIssuanceCostIncludedInAccountsPayable" xlink:label="ymab_NoncashOrPartialNoncashTransactionCommonStockIssuanceCostIncludedInAccountsPayable_637092576538457033" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncashInvestingAndFinancingItemsAbstract_637092576538457033" xlink:to="ymab_NoncashOrPartialNoncashTransactionCommonStockIssuanceCostIncludedInAccountsPayable_637092576538457033" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_NoncashOrPartialNoncashTransactionDeferredOfferingCostsIncludedInOtherAssetsAndAccountsPayableAndAccruedLiabilitiesAndOther" xlink:label="ymab_NoncashOrPartialNoncashTransactionDeferredOfferingCostsIncludedInOtherAssetsAndAccountsPayableAndAccruedLiabilitiesAndOther_637092576538457033" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncashInvestingAndFinancingItemsAbstract_637092576538457033" xlink:to="ymab_NoncashOrPartialNoncashTransactionDeferredOfferingCostsIncludedInOtherAssetsAndAccountsPayableAndAccruedLiabilitiesAndOther_637092576538457033" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureOrganizationAndDescriptionOfBusiness" xlink:type="extended" xlink:title="10101 - Disclosure - ORGANIZATION AND DESCRIPTION OF BUSINESS" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_OrganizationAndDescriptionOfBusinessAbstract" xlink:label="ymab_OrganizationAndDescriptionOfBusinessAbstract_636748512223779268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NatureOfOperations" xlink:label="us-gaap_NatureOfOperations_637092576538467061" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_OrganizationAndDescriptionOfBusinessAbstract_636748512223779268" xlink:to="us-gaap_NatureOfOperations_637092576538467061" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureBasisOfPresentation" xlink:type="extended" xlink:title="10201 - Disclosure - BASIS OF PRESENTATION" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_BasisOfPresentationAbstract" xlink:label="ymab_BasisOfPresentationAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BasisOfAccounting" xlink:label="us-gaap_BasisOfAccounting_637092576538467061" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_BasisOfPresentationAbstract" xlink:to="us-gaap_BasisOfAccounting_637092576538467061" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureSummaryOfSignificantAccountingPolicies" xlink:type="extended" xlink:title="10301 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="us-gaap_AccountingPoliciesAbstract_636748512224091268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SignificantAccountingPoliciesTextBlock" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_637092576538467061" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccountingPoliciesAbstract_636748512224091268" xlink:to="us-gaap_SignificantAccountingPoliciesTextBlock_637092576538467061" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureNetLossPerShare" xlink:type="extended" xlink:title="10401 - Disclosure - NET LOSS PER SHARE" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="us-gaap_EarningsPerShareAbstract_636748512224091268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarningsPerShareTextBlock" xlink:label="us-gaap_EarningsPerShareTextBlock_637092576538467061" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EarningsPerShareAbstract_636748512224091268" xlink:to="us-gaap_EarningsPerShareTextBlock_637092576538467061" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="9" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureAccruedLiabilities" xlink:type="extended" xlink:title="10501 - Disclosure - ACCRUED LIABILITIES" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:label="us-gaap_AccruedLiabilitiesCurrentAndNoncurrentAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_637092576538467061" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:to="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_637092576538467061" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitments" xlink:type="extended" xlink:title="10601 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CollaborativeArrangementDisclosureTextBlock" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock_637092576538467061" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_CollaborativeArrangementDisclosureTextBlock_637092576538467061" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureStockholdersEquity" xlink:type="extended" xlink:title="10701 - Disclosure - STOCKHOLDERS' EQUITY" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityAbstract" xlink:label="us-gaap_EquityAbstract_636748512224091268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_637092576538477086" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract_636748512224091268" xlink:to="us-gaap_StockholdersEquityNoteDisclosureTextBlock_637092576538477086" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureShareBasedCompensation" xlink:type="extended" xlink:title="10801 - Disclosure - SHARE-BASED COMPENSATION" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_636748512224091268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_637092576538477086" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_636748512224091268" xlink:to="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_637092576538477086" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureRelatedPartyTransactions" xlink:type="extended" xlink:title="10901 - Disclosure - RELATED PARTY TRANSACTIONS" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RelatedPartyTransactionsAbstract" xlink:label="us-gaap_RelatedPartyTransactionsAbstract_636748512807219268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_637092576538477086" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_RelatedPartyTransactionsAbstract_636748512807219268" xlink:to="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_637092576538477086" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureIncomeTaxes" xlink:type="extended" xlink:title="11001 - Disclosure - INCOME TAXES" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_636748512807219268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxDisclosureTextBlock" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_637092576538477086" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeTaxDisclosureAbstract_636748512807219268" xlink:to="us-gaap_IncomeTaxDisclosureTextBlock_637092576538477086" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureOtherBenefits" xlink:type="extended" xlink:title="11101 - Disclosure - OTHER BENEFITS" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_OtherBenefitsDisclosureAbstract" xlink:label="ymab_OtherBenefitsDisclosureAbstract_636748512807219268" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_OtherBenefitsDisclosureTextBlock" xlink:label="ymab_OtherBenefitsDisclosureTextBlock_637092576538477086" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_OtherBenefitsDisclosureAbstract_636748512807219268" xlink:to="ymab_OtherBenefitsDisclosureTextBlock_637092576538477086" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureSubsequentEvents" xlink:type="extended" xlink:title="11201 - Disclosure - SUBSEQUENT EVENTS" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="us-gaap_SubsequentEventsAbstract_636748512807219268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="us-gaap_SubsequentEventsTextBlock_637092576538477086" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventsAbstract_636748512807219268" xlink:to="us-gaap_SubsequentEventsTextBlock_637092576538477086" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureSummaryOfSignificantAccountingPoliciesPolicies" xlink:type="extended" xlink:title="20302 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="us-gaap_AccountingPoliciesAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeLeasesPolicyTextBlock" xlink:label="us-gaap_LesseeLeasesPolicyTextBlock_637092576538487111" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_LesseeLeasesPolicyTextBlock_637092576538487111" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_UseOfEstimates" xlink:label="us-gaap_UseOfEstimates_637092576538487111" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_UseOfEstimates_637092576538487111" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentReportingPolicyPolicyTextBlock" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_637092576538497139" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_SegmentReportingPolicyPolicyTextBlock_637092576538497139" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_637092576538497139" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_637092576538497139" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="5" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureNetLossPerShareTables" xlink:type="extended" xlink:title="30403 - Disclosure - NET LOSS PER SHARE (Tables)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="us-gaap_EarningsPerShareAbstract_636748512224091268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_637092576538497139" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EarningsPerShareAbstract_636748512224091268" xlink:to="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_637092576538497139" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureAccruedLiabilitiesTables" xlink:type="extended" xlink:title="30503 - Disclosure - ACCRUED LIABILITIES (Tables)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:label="us-gaap_AccruedLiabilitiesCurrentAndNoncurrentAbstract_636748512224091268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock" xlink:label="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_637092576538497139" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccruedLiabilitiesCurrentAndNoncurrentAbstract_636748512224091268" xlink:to="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_637092576538497139" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsTables" xlink:type="extended" xlink:title="30603 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS (Tables)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_637092576538497139" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_637092576538497139" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock" xlink:label="us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock_637092576538497139" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock_637092576538497139" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureShareBasedCompensationTables" xlink:type="extended" xlink:title="30803 - Disclosure - SHARE-BASED COMPENSATION (Tables)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_637092576538497139" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:to="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_637092576538497139" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock" xlink:label="us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock_637092576538497139" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:to="us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock_637092576538497139" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureOrganizationAndDescriptionOfBusinessDetails" xlink:type="extended" xlink:title="40101 - Disclosure - ORGANIZATION AND DESCRIPTION OF BUSINESS (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_OrganizationAndDescriptionOfBusinessAbstract" xlink:label="ymab_OrganizationAndDescriptionOfBusinessAbstract" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_NumberOfProductDevelopmentPrograms" xlink:label="ymab_NumberOfProductDevelopmentPrograms_637092576538507186" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_OrganizationAndDescriptionOfBusinessAbstract" xlink:to="ymab_NumberOfProductDevelopmentPrograms_637092576538507186" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureBasisOfPresentationDetails" xlink:type="extended" xlink:title="40201 - Disclosure - BASIS OF PRESENTATION (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_BasisOfPresentationAbstract" xlink:label="ymab_BasisOfPresentationAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable" xlink:label="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_637092576538507186" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_BasisOfPresentationAbstract" xlink:to="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_637092576538507186" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_637092576538507186" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_637092576538507186" xlink:to="us-gaap_SubsidiarySaleOfStockAxis_637092576538507186" order="1" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_637092576538507186" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiarySaleOfStockAxis_637092576538507186" xlink:to="us-gaap_SaleOfStockNameOfTransactionDomain_637092576538507186" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_FollowOnShelfPublicOfferingMember" xlink:label="ymab_FollowOnShelfPublicOfferingMember_637092576538507186" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SaleOfStockNameOfTransactionDomain_637092576538507186" xlink:to="ymab_FollowOnShelfPublicOfferingMember_637092576538507186" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="us-gaap_SubsequentEventTypeAxis_637092576538517196" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_637092576538507186" xlink:to="us-gaap_SubsequentEventTypeAxis_637092576538517196" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="us-gaap_SubsequentEventTypeDomain_637092576538517196" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventTypeAxis_637092576538517196" xlink:to="us-gaap_SubsequentEventTypeDomain_637092576538517196" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="us-gaap_SubsequentEventMember_637092576538517196" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventTypeDomain_637092576538517196" xlink:to="us-gaap_SubsequentEventMember_637092576538517196" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsidiarySaleOfStockLineItems" xlink:label="us-gaap_SubsidiarySaleOfStockLineItems_637092576538517196" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_637092576538507186" xlink:to="us-gaap_SubsidiarySaleOfStockLineItems_637092576538517196" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_637092576538517196" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiarySaleOfStockLineItems_637092576538517196" xlink:to="us-gaap_RetainedEarningsAccumulatedDeficit_637092576538517196" order="1" use="optional" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="8" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_637092576538517196" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiarySaleOfStockLineItems_637092576538517196" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_637092576538517196" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_637092576538517196" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiarySaleOfStockLineItems_637092576538517196" xlink:to="us-gaap_ProceedsFromIssuanceOfCommonStock_637092576538517196" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="7" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureSummaryOfSignificantAccountingPoliciesLeasesAndSegmentsDetails" xlink:type="extended" xlink:title="40301 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Leases and Segments (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="us-gaap_AccountingPoliciesAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ResidualValueOfLeasedAsset" xlink:label="us-gaap_ResidualValueOfLeasedAsset_637092576538527225" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_ResidualValueOfLeasedAsset_637092576538527225" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NumberOfOperatingSegments" xlink:label="us-gaap_NumberOfOperatingSegments_637092576538527225" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_NumberOfOperatingSegments_637092576538527225" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureSummaryOfSignificantAccountingPoliciesRecentlyIssuedAccountingPronouncementsDetails" xlink:type="extended" xlink:title="40302 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Recently issued accounting pronouncements (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="us-gaap_AccountingPoliciesAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable" xlink:label="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_637092576538537242" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_637092576538537242" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_637092576538537242" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_637092576538537242" xlink:to="us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_637092576538537242" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="us-gaap_TypeOfAdoptionMember_637092576538537242" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_637092576538537242" xlink:to="us-gaap_TypeOfAdoptionMember_637092576538537242" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountingStandardsUpdate201602Member" xlink:label="us-gaap_AccountingStandardsUpdate201602Member_637092576538537242" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_TypeOfAdoptionMember_637092576538537242" xlink:to="us-gaap_AccountingStandardsUpdate201602Member_637092576538537242" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RestatementAxis" xlink:label="srt_RestatementAxis_637092576538537242" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_637092576538537242" xlink:to="srt_RestatementAxis_637092576538537242" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RestatementDomain" xlink:label="srt_RestatementDomain_637092576538537242" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_RestatementAxis_637092576538537242" xlink:to="srt_RestatementDomain_637092576538537242" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RestatementAdjustmentMember" xlink:label="srt_RestatementAdjustmentMember_637092576538537242" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_RestatementDomain_637092576538537242" xlink:to="srt_RestatementAdjustmentMember_637092576538537242" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems" xlink:label="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_637092576538547271" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_637092576538537242" xlink:to="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_637092576538547271" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdopted" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdopted_637092576538547271" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_637092576538547271" xlink:to="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdopted_637092576538547271" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateTransitionOptionElectedFixedList" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateTransitionOptionElectedFixedList_637092576538547271" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_637092576538547271" xlink:to="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateTransitionOptionElectedFixedList_637092576538547271" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NewAccountingPronouncementOrChangeInAccountingPrinciplePriorPeriodNotRestated" xlink:label="us-gaap_NewAccountingPronouncementOrChangeInAccountingPrinciplePriorPeriodNotRestated_637092576538547271" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_637092576538547271" xlink:to="us-gaap_NewAccountingPronouncementOrChangeInAccountingPrinciplePriorPeriodNotRestated_637092576538547271" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LeasePracticalExpedientsPackage" xlink:label="us-gaap_LeasePracticalExpedientsPackage_637092576538547271" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_637092576538547271" xlink:to="us-gaap_LeasePracticalExpedientsPackage_637092576538547271" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseLiability" xlink:label="us-gaap_OperatingLeaseLiability_637092576538547271" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_637092576538547271" xlink:to="us-gaap_OperatingLeaseLiability_637092576538547271" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_637092576538547271" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_637092576538547271" xlink:to="us-gaap_OperatingLeaseRightOfUseAsset_637092576538547271" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_OperatingLeaseNumberOfLeaseAgreements" xlink:label="ymab_OperatingLeaseNumberOfLeaseAgreements_637092576538557299" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_637092576538547271" xlink:to="ymab_OperatingLeaseNumberOfLeaseAgreements_637092576538557299" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_OperatingLeaseLiabilityAdditions" xlink:label="ymab_OperatingLeaseLiabilityAdditions_637092576538557299" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_637092576538547271" xlink:to="ymab_OperatingLeaseLiabilityAdditions_637092576538557299" order="8" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_OperatingLeaseRightOfUseAssetAdditions" xlink:label="ymab_OperatingLeaseRightOfUseAssetAdditions_637092576538557299" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_637092576538547271" xlink:to="ymab_OperatingLeaseRightOfUseAssetAdditions_637092576538557299" order="9" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureNetLossPerShareBasicAndDilutedDetails" xlink:type="extended" xlink:title="40401 - Disclosure - NET LOSS PER SHARE - Basic and diluted (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="us-gaap_EarningsPerShareAbstract_636748512224559268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss_637092576538567324" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EarningsPerShareAbstract_636748512224559268" xlink:to="us-gaap_NetIncomeLoss_637092576538567324" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:label="us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted_637092576538567324" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EarningsPerShareAbstract_636748512224559268" xlink:to="us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted_637092576538567324" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarningsPerShareBasicAndDiluted" xlink:label="us-gaap_EarningsPerShareBasicAndDiluted_637092576538567324" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EarningsPerShareAbstract_636748512224559268" xlink:to="us-gaap_EarningsPerShareBasicAndDiluted_637092576538567324" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="6" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureNetLossPerShareAntiDilutiveSecuritiesDetails" xlink:type="extended" xlink:title="40402 - Disclosure - NET LOSS PER SHARE - Anti-dilutive securities (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="us-gaap_EarningsPerShareAbstract_636748512224559268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_637092576538567324" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EarningsPerShareAbstract_636748512224559268" xlink:to="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_637092576538567324" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureAccruedLiabilitiesDetails" xlink:type="extended" xlink:title="40501 - Disclosure - ACCRUED LIABILITIES (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:label="us-gaap_AccruedLiabilitiesCurrentAndNoncurrentAbstract_636748512224559268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:label="us-gaap_AccruedLiabilitiesCurrentAbstract_637092576538567324" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccruedLiabilitiesCurrentAndNoncurrentAbstract_636748512224559268" xlink:to="us-gaap_AccruedLiabilitiesCurrentAbstract_637092576538567324" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedMilestonePaymentsAndAccruedRoyaltiesCurrent" xlink:label="ymab_AccruedMilestonePaymentsAndAccruedRoyaltiesCurrent_637092576538577349" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract_637092576538567324" xlink:to="ymab_AccruedMilestonePaymentsAndAccruedRoyaltiesCurrent_637092576538577349" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedClinicalCostsCurrent" xlink:label="ymab_AccruedClinicalCostsCurrent_637092576538577349" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract_637092576538567324" xlink:to="ymab_AccruedClinicalCostsCurrent_637092576538577349" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedCompensationAndBoardFeesCurrent" xlink:label="ymab_AccruedCompensationAndBoardFeesCurrent_637092576538577349" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract_637092576538567324" xlink:to="ymab_AccruedCompensationAndBoardFeesCurrent_637092576538577349" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccruedRentCurrent" xlink:label="us-gaap_AccruedRentCurrent_637092576538577349" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract_637092576538567324" xlink:to="us-gaap_AccruedRentCurrent_637092576538577349" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedManufacturingCostsCurrent" xlink:label="ymab_AccruedManufacturingCostsCurrent_637092576538577349" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract_637092576538567324" xlink:to="ymab_AccruedManufacturingCostsCurrent_637092576538577349" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherAccruedLiabilitiesCurrent" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_637092576538577349" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract_637092576538567324" xlink:to="us-gaap_OtherAccruedLiabilitiesCurrent_637092576538577349" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="us-gaap_AccruedLiabilitiesCurrent_637092576538577349" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract_637092576538567324" xlink:to="us-gaap_AccruedLiabilitiesCurrent_637092576538577349" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsDetails" xlink:type="extended" xlink:title="40601 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_NumberOfLicenseAgreements" xlink:label="ymab_NumberOfLicenseAgreements_637092576538587399" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="ymab_NumberOfLicenseAgreements_637092576538587399" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsMskLicenseAgreementDetails" xlink:type="extended" xlink:title="40602 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS - MSK License Agreement (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" xlink:label="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538587399" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538587399" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="us-gaap_TypeOfArrangementAxis_637092576538587399" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538587399" xlink:to="us-gaap_TypeOfArrangementAxis_637092576538587399" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538587399" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_TypeOfArrangementAxis_637092576538587399" xlink:to="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538587399" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NoncollaborativeArrangementTransactionsMember" xlink:label="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538587399" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538587399" xlink:to="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538587399" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_MskLicenseAgreementMember" xlink:label="ymab_MskLicenseAgreementMember_637092576538587399" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538587399" xlink:to="ymab_MskLicenseAgreementMember_637092576538587399" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationAxis" xlink:label="us-gaap_BalanceSheetLocationAxis_637092576538597406" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538587399" xlink:to="us-gaap_BalanceSheetLocationAxis_637092576538597406" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="us-gaap_BalanceSheetLocationDomain_637092576538597406" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_BalanceSheetLocationAxis_637092576538597406" xlink:to="us-gaap_BalanceSheetLocationDomain_637092576538597406" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedLiabilitiesCurrentMember" xlink:label="ymab_AccruedLiabilitiesCurrentMember_637092576538597406" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_BalanceSheetLocationDomain_637092576538597406" xlink:to="ymab_AccruedLiabilitiesCurrentMember_637092576538597406" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedLiabilitiesNoncurrentMember" xlink:label="ymab_AccruedLiabilitiesNoncurrentMember_637092576538597406" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_BalanceSheetLocationDomain_637092576538597406" xlink:to="ymab_AccruedLiabilitiesNoncurrentMember_637092576538597406" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538587399" xlink:to="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_StockIssuedDuringPeriodSharesNewIssuesToStrategicPartner" xlink:label="ymab_StockIssuedDuringPeriodSharesNewIssuesToStrategicPartner_637092576538597406" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="ymab_StockIssuedDuringPeriodSharesNewIssuesToStrategicPartner_637092576538597406" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeAnnualMinimumRoyaltiesPayableFromFifthAnniversary" xlink:label="ymab_ArrangementOtherThanCollaborativeAnnualMinimumRoyaltiesPayableFromFifthAnniversary_637092576538597406" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="ymab_ArrangementOtherThanCollaborativeAnnualMinimumRoyaltiesPayableFromFifthAnniversary_637092576538597406" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RoyaltyExpense" xlink:label="us-gaap_RoyaltyExpense_637092576538597406" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="us-gaap_RoyaltyExpense_637092576538597406" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccruedRoyaltiesCurrent" xlink:label="us-gaap_AccruedRoyaltiesCurrent_637092576538607431" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="us-gaap_AccruedRoyaltiesCurrent_637092576538607431" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedRoyaltiesNoncurrent" xlink:label="ymab_AccruedRoyaltiesNoncurrent_637092576538607431" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="ymab_AccruedRoyaltiesNoncurrent_637092576538607431" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeClinicalMilestonePaymentsDue" xlink:label="ymab_ArrangementOtherThanCollaborativeClinicalMilestonePaymentsDue_637092576538607431" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="ymab_ArrangementOtherThanCollaborativeClinicalMilestonePaymentsDue_637092576538607431" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeRegulatoryMilestonePaymentsDue" xlink:label="ymab_ArrangementOtherThanCollaborativeRegulatoryMilestonePaymentsDue_637092576538607431" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="ymab_ArrangementOtherThanCollaborativeRegulatoryMilestonePaymentsDue_637092576538607431" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeSalesBasedMilestonePaymentsDue" xlink:label="ymab_ArrangementOtherThanCollaborativeSalesBasedMilestonePaymentsDue_637092576538607431" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="ymab_ArrangementOtherThanCollaborativeSalesBasedMilestonePaymentsDue_637092576538607431" order="8" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeClinicalMilestoneExpense" xlink:label="ymab_ArrangementOtherThanCollaborativeClinicalMilestoneExpense_637092576538607431" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="ymab_ArrangementOtherThanCollaborativeClinicalMilestoneExpense_637092576538607431" order="9" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeMilestonePayment" xlink:label="ymab_ArrangementOtherThanCollaborativeMilestonePayment_637092576538617455" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="ymab_ArrangementOtherThanCollaborativeMilestonePayment_637092576538617455" order="10" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedMilestonePaymentsCurrent" xlink:label="ymab_AccruedMilestonePaymentsCurrent_637092576538617455" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="ymab_AccruedMilestonePaymentsCurrent_637092576538617455" order="11" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedMilestonePaymentsNoncurrent" xlink:label="ymab_AccruedMilestonePaymentsNoncurrent_637092576538617455" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538597406" xlink:to="ymab_AccruedMilestonePaymentsNoncurrent_637092576538617455" order="12" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsCd33LicenseAgreementDetails" xlink:type="extended" xlink:title="40603 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS - CD33 License Agreement (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" xlink:label="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538627487" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538627487" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="us-gaap_TypeOfArrangementAxis_637092576538627487" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538627487" xlink:to="us-gaap_TypeOfArrangementAxis_637092576538627487" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538627487" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_TypeOfArrangementAxis_637092576538627487" xlink:to="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538627487" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NoncollaborativeArrangementTransactionsMember" xlink:label="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538627487" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538627487" xlink:to="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538627487" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_Cd33LicenseAgreementMember" xlink:label="ymab_Cd33LicenseAgreementMember_637092576538627487" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538627487" xlink:to="ymab_Cd33LicenseAgreementMember_637092576538627487" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationAxis" xlink:label="us-gaap_BalanceSheetLocationAxis_637092576538627487" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538627487" xlink:to="us-gaap_BalanceSheetLocationAxis_637092576538627487" order="2" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="us-gaap_BalanceSheetLocationDomain_637092576538637512" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_BalanceSheetLocationAxis_637092576538627487" xlink:to="us-gaap_BalanceSheetLocationDomain_637092576538637512" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedLiabilitiesCurrentMember" xlink:label="ymab_AccruedLiabilitiesCurrentMember_637092576538637512" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_BalanceSheetLocationDomain_637092576538637512" xlink:to="ymab_AccruedLiabilitiesCurrentMember_637092576538637512" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedLiabilitiesNoncurrentMember" xlink:label="ymab_AccruedLiabilitiesNoncurrentMember_637092576538637512" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_BalanceSheetLocationDomain_637092576538637512" xlink:to="ymab_AccruedLiabilitiesNoncurrentMember_637092576538637512" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538627487" xlink:to="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeAnnualMinimumRoyaltiesPayable" xlink:label="ymab_ArrangementOtherThanCollaborativeAnnualMinimumRoyaltiesPayable_637092576538637512" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" xlink:to="ymab_ArrangementOtherThanCollaborativeAnnualMinimumRoyaltiesPayable_637092576538637512" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeAnnualMinimumRoyaltiesPayableFromTenthAnniversary" xlink:label="ymab_ArrangementOtherThanCollaborativeAnnualMinimumRoyaltiesPayableFromTenthAnniversary_637092576538637512" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" xlink:to="ymab_ArrangementOtherThanCollaborativeAnnualMinimumRoyaltiesPayableFromTenthAnniversary_637092576538637512" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeClinicalMilestonePaymentsDue" xlink:label="ymab_ArrangementOtherThanCollaborativeClinicalMilestonePaymentsDue_637092576538637512" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" xlink:to="ymab_ArrangementOtherThanCollaborativeClinicalMilestonePaymentsDue_637092576538637512" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeRegulatoryMilestonePaymentsDue" xlink:label="ymab_ArrangementOtherThanCollaborativeRegulatoryMilestonePaymentsDue_637092576538637512" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" xlink:to="ymab_ArrangementOtherThanCollaborativeRegulatoryMilestonePaymentsDue_637092576538637512" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeSalesBasedMilestonePaymentsDue" xlink:label="ymab_ArrangementOtherThanCollaborativeSalesBasedMilestonePaymentsDue_637092576538637512" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" xlink:to="ymab_ArrangementOtherThanCollaborativeSalesBasedMilestonePaymentsDue_637092576538637512" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeClinicalMilestoneExpense" xlink:label="ymab_ArrangementOtherThanCollaborativeClinicalMilestoneExpense_637092576538637512" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" xlink:to="ymab_ArrangementOtherThanCollaborativeClinicalMilestoneExpense_637092576538637512" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeClinicalMilestonePayment" xlink:label="ymab_ArrangementOtherThanCollaborativeClinicalMilestonePayment_637092576538687666" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" xlink:to="ymab_ArrangementOtherThanCollaborativeClinicalMilestonePayment_637092576538687666" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedMilestonePayments" xlink:label="ymab_AccruedMilestonePayments_637092576538687666" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" xlink:to="ymab_AccruedMilestonePayments_637092576538687666" order="8" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedMilestonePaymentsCurrent" xlink:label="ymab_AccruedMilestonePaymentsCurrent_637092576538687666" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" xlink:to="ymab_AccruedMilestonePaymentsCurrent_637092576538687666" order="9" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_AccruedMilestonePaymentsNoncurrent" xlink:label="ymab_AccruedMilestonePaymentsNoncurrent_637092576538687666" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538637512" xlink:to="ymab_AccruedMilestonePaymentsNoncurrent_637092576538687666" order="10" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsMabvaxSublicenseAgreementDetails" xlink:type="extended" xlink:title="40604 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS - MabVax sublicense agreement (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" xlink:label="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538697676" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="us-gaap_TypeOfArrangementAxis_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538697676" xlink:to="us-gaap_TypeOfArrangementAxis_637092576538697676" order="1" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_TypeOfArrangementAxis_637092576538697676" xlink:to="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538697676" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NoncollaborativeArrangementTransactionsMember" xlink:label="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538697676" xlink:to="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538697676" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_MabvaxSublicenseAgreementMember" xlink:label="ymab_MabvaxSublicenseAgreementMember_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538697676" xlink:to="ymab_MabvaxSublicenseAgreementMember_637092576538697676" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538697676" xlink:to="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538697676" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeLicenseFeePaid" xlink:label="ymab_ArrangementOtherThanCollaborativeLicenseFeePaid_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538697676" xlink:to="ymab_ArrangementOtherThanCollaborativeLicenseFeePaid_637092576538697676" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeLicenseFeeExpense" xlink:label="ymab_ArrangementOtherThanCollaborativeLicenseFeeExpense_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538697676" xlink:to="ymab_ArrangementOtherThanCollaborativeLicenseFeeExpense_637092576538697676" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeAccruedContinuationFeeExpense" xlink:label="ymab_ArrangementOtherThanCollaborativeAccruedContinuationFeeExpense_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538697676" xlink:to="ymab_ArrangementOtherThanCollaborativeAccruedContinuationFeeExpense_637092576538697676" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeContinuationFeePaid" xlink:label="ymab_ArrangementOtherThanCollaborativeContinuationFeePaid_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538697676" xlink:to="ymab_ArrangementOtherThanCollaborativeContinuationFeePaid_637092576538697676" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeDevelopmentMilestonePaymentsDue" xlink:label="ymab_ArrangementOtherThanCollaborativeDevelopmentMilestonePaymentsDue_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538697676" xlink:to="ymab_ArrangementOtherThanCollaborativeDevelopmentMilestonePaymentsDue_637092576538697676" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsOtherAgreementsDetails" xlink:type="extended" xlink:title="40605 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS - Other agreements (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" xlink:label="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538697676" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538697676" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_TitleOfIndividualAxis" xlink:label="srt_TitleOfIndividualAxis_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538697676" xlink:to="srt_TitleOfIndividualAxis_637092576538707719" order="1" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="srt_TitleOfIndividualWithRelationshipToEntityDomain_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_TitleOfIndividualAxis_637092576538707719" xlink:to="srt_TitleOfIndividualWithRelationshipToEntityDomain_637092576538707719" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ResearchersEmployeesOfMskMember" xlink:label="ymab_ResearchersEmployeesOfMskMember_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_TitleOfIndividualWithRelationshipToEntityDomain_637092576538707719" xlink:to="ymab_ResearchersEmployeesOfMskMember_637092576538707719" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="us-gaap_TypeOfArrangementAxis_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538697676" xlink:to="us-gaap_TypeOfArrangementAxis_637092576538707719" order="2" use="optional" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_TypeOfArrangementAxis_637092576538707719" xlink:to="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538707719" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NoncollaborativeArrangementTransactionsMember" xlink:label="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ArrangementsAndNonarrangementTransactionsMember_637092576538707719" xlink:to="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538707719" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_SponsoredResearchAgreementMember" xlink:label="ymab_SponsoredResearchAgreementMember_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538707719" xlink:to="ymab_SponsoredResearchAgreementMember_637092576538707719" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_MasterDataServicesAgreementMember" xlink:label="ymab_MasterDataServicesAgreementMember_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538707719" xlink:to="ymab_MasterDataServicesAgreementMember_637092576538707719" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_MasterClinicalTrialAgreementMember" xlink:label="ymab_MasterClinicalTrialAgreementMember_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538707719" xlink:to="ymab_MasterClinicalTrialAgreementMember_637092576538707719" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_CoreFacilityServiceAgreementMember" xlink:label="ymab_CoreFacilityServiceAgreementMember_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538707719" xlink:to="ymab_CoreFacilityServiceAgreementMember_637092576538707719" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_Cb33SponsoredResearchAgreementMember" xlink:label="ymab_Cb33SponsoredResearchAgreementMember_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_NoncollaborativeArrangementTransactionsMember_637092576538707719" xlink:to="ymab_Cb33SponsoredResearchAgreementMember_637092576538707719" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_637092576538697676" xlink:to="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538707719" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeResearchServicePeriod" xlink:label="ymab_ArrangementOtherThanCollaborativeResearchServicePeriod_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538707719" xlink:to="ymab_ArrangementOtherThanCollaborativeResearchServicePeriod_637092576538707719" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ArrangementOtherThanCollaborativeNumberOfServiceAgreements" xlink:label="ymab_ArrangementOtherThanCollaborativeNumberOfServiceAgreements_637092576538707719" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538707719" xlink:to="ymab_ArrangementOtherThanCollaborativeNumberOfServiceAgreements_637092576538707719" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="us-gaap_ResearchAndDevelopmentExpense_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538707719" xlink:to="us-gaap_ResearchAndDevelopmentExpense_637092576538717747" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_NumberOfIndividuals" xlink:label="ymab_NumberOfIndividuals_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_637092576538707719" xlink:to="ymab_NumberOfIndividuals_637092576538717747" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsLeaseAgreementsDetails" xlink:type="extended" xlink:title="40606 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS - Lease agreements (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeLeaseDescriptionTable" xlink:label="us-gaap_LesseeLeaseDescriptionTable_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_LesseeLeaseDescriptionTable_637092576538717747" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionTable_637092576538717747" xlink:to="us-gaap_PropertyPlantAndEquipmentByTypeAxis_637092576538717747" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_PropertyPlantAndEquipmentByTypeAxis_637092576538717747" xlink:to="us-gaap_PropertyPlantAndEquipmentTypeDomain_637092576538717747" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LeaseArrangementLaboratoryNewJerseyMember" xlink:label="ymab_LeaseArrangementLaboratoryNewJerseyMember_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_PropertyPlantAndEquipmentTypeDomain_637092576538717747" xlink:to="ymab_LeaseArrangementLaboratoryNewJerseyMember_637092576538717747" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LeaseArrangementCorporateHeadquartersNewYorkMember" xlink:label="ymab_LeaseArrangementCorporateHeadquartersNewYorkMember_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_PropertyPlantAndEquipmentTypeDomain_637092576538717747" xlink:to="ymab_LeaseArrangementCorporateHeadquartersNewYorkMember_637092576538717747" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LeaseArrangementOfficeSpaceDenmarkMember" xlink:label="ymab_LeaseArrangementOfficeSpaceDenmarkMember_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_PropertyPlantAndEquipmentTypeDomain_637092576538717747" xlink:to="ymab_LeaseArrangementOfficeSpaceDenmarkMember_637092576538717747" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeLeaseDescriptionLineItems" xlink:label="us-gaap_LesseeLeaseDescriptionLineItems_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionTable_637092576538717747" xlink:to="us-gaap_LesseeLeaseDescriptionLineItems_637092576538717747" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AreaOfRealEstateProperty" xlink:label="us-gaap_AreaOfRealEstateProperty_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionLineItems_637092576538717747" xlink:to="us-gaap_AreaOfRealEstateProperty_637092576538717747" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseTermOfContract" xlink:label="us-gaap_LesseeOperatingLeaseTermOfContract_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionLineItems_637092576538717747" xlink:to="us-gaap_LesseeOperatingLeaseTermOfContract_637092576538717747" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseExistenceOfOptionToExtend" xlink:label="us-gaap_LesseeOperatingLeaseExistenceOfOptionToExtend_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionLineItems_637092576538717747" xlink:to="us-gaap_LesseeOperatingLeaseExistenceOfOptionToExtend_637092576538717747" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseRenewalTerm" xlink:label="us-gaap_LesseeOperatingLeaseRenewalTerm_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionLineItems_637092576538717747" xlink:to="us-gaap_LesseeOperatingLeaseRenewalTerm_637092576538717747" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_FixedRentPayablePerAnnum" xlink:label="ymab_FixedRentPayablePerAnnum_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionLineItems_637092576538717747" xlink:to="ymab_FixedRentPayablePerAnnum_637092576538717747" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LeasePayablePerMonth" xlink:label="ymab_LeasePayablePerMonth_637092576538717747" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionLineItems_637092576538717747" xlink:to="ymab_LeasePayablePerMonth_637092576538717747" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsLeaseCostsDetails" xlink:type="extended" xlink:title="40607 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS - Lease costs (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeLeaseDescriptionTable" xlink:label="us-gaap_LesseeLeaseDescriptionTable_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_LesseeLeaseDescriptionTable_637092576538727754" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="us-gaap_IncomeStatementLocationAxis_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionTable_637092576538727754" xlink:to="us-gaap_IncomeStatementLocationAxis_637092576538727754" order="1" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="us-gaap_IncomeStatementLocationDomain_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeStatementLocationAxis_637092576538727754" xlink:to="us-gaap_IncomeStatementLocationDomain_637092576538727754" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ResearchAndDevelopmentExpenseMember" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeStatementLocationDomain_637092576538727754" xlink:to="us-gaap_ResearchAndDevelopmentExpenseMember_637092576538727754" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GeneralAndAdministrativeExpenseMember" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeStatementLocationDomain_637092576538727754" xlink:to="us-gaap_GeneralAndAdministrativeExpenseMember_637092576538727754" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeLeaseDescriptionLineItems" xlink:label="us-gaap_LesseeLeaseDescriptionLineItems_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionTable_637092576538727754" xlink:to="us-gaap_LesseeLeaseDescriptionLineItems_637092576538727754" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseCost" xlink:label="us-gaap_OperatingLeaseCost_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionLineItems_637092576538727754" xlink:to="us-gaap_OperatingLeaseCost_637092576538727754" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeasesRentExpenseNet" xlink:label="us-gaap_OperatingLeasesRentExpenseNet_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionLineItems_637092576538727754" xlink:to="us-gaap_OperatingLeasesRentExpenseNet_637092576538727754" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeasePayments" xlink:label="us-gaap_OperatingLeasePayments_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_LesseeLeaseDescriptionLineItems_637092576538727754" xlink:to="us-gaap_OperatingLeasePayments_637092576538727754" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsLeaseMaturitiesDetails" xlink:type="extended" xlink:title="40608 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS - Lease maturities (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract" xlink:label="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_637092576538727754" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_637092576538727754" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_637092576538727754" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_637092576538727754" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_637092576538727754" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_637092576538727754" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_637092576538727754" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_637092576538727754" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_637092576538727754" order="8" use="optional" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseLiability" xlink:label="us-gaap_OperatingLeaseLiability_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_OperatingLeaseLiability_637092576538727754" order="9" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitments2018LeaseMaturitiesDetails" xlink:type="extended" xlink:title="40609 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS - 2018 Lease maturities (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract_637084619412597918" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_637092576538727754" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract_637084619412597918" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_637092576538727754" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_637092576538737779" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_637092576538737779" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_637092576538737779" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_637092576538737779" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_637092576538737779" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_637092576538737779" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_637092576538737779" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_637092576538737779" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_637092576538737779" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_637092576538737779" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_637092576538737779" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_637092576538737779" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDue" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDue_637092576538737779" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDue_637092576538737779" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_637092576538737779" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_637092576538737779" order="8" use="optional" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDue" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDue_6370925765387377791" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_637092576538727754" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDue_6370925765387377791" order="9" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureLicenseAgreementsAndCommitmentsLeaseTermAndDiscountRateDetails" xlink:type="extended" xlink:title="40610 - Disclosure - LICENSE AGREEMENTS AND COMMITMENTS - Lease term and discount rate (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:label="ymab_LicenseAgreementsAndCommitmentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_637092576538737779" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_637092576538737779" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_637092576538737779" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_LicenseAgreementsAndCommitmentsAbstract" xlink:to="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_637092576538737779" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureStockholdersEquityAuthorizedCommonAndPreferredStockDetails" xlink:type="extended" xlink:title="40701 - Disclosure - STOCKHOLDERS' EQUITY - Authorized, Common and Preferred Stock (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityAbstract" xlink:label="us-gaap_EquityAbstract" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_TotalSharesAuthorized" xlink:label="ymab_TotalSharesAuthorized_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract" xlink:to="ymab_TotalSharesAuthorized_637092576538747826" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="us-gaap_CommonStockSharesAuthorized_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract" xlink:to="us-gaap_CommonStockSharesAuthorized_637092576538747826" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract" xlink:to="us-gaap_CommonStockParOrStatedValuePerShare_637092576538747826" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="us-gaap_PreferredStockSharesAuthorized_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract" xlink:to="us-gaap_PreferredStockSharesAuthorized_637092576538747826" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract" xlink:to="us-gaap_PreferredStockParOrStatedValuePerShare_637092576538747826" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_NumberOfVotesPerCommonStock" xlink:label="ymab_NumberOfVotesPerCommonStock_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract" xlink:to="ymab_NumberOfVotesPerCommonStock_637092576538747826" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DividendsCommonStock" xlink:label="us-gaap_DividendsCommonStock_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract" xlink:to="us-gaap_DividendsCommonStock_637092576538747826" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockSharesIssued" xlink:label="us-gaap_CommonStockSharesIssued_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract" xlink:to="us-gaap_CommonStockSharesIssued_637092576538747826" order="8" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PreferredStockSharesIssued" xlink:label="us-gaap_PreferredStockSharesIssued_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract" xlink:to="us-gaap_PreferredStockSharesIssued_637092576538747826" order="9" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="7" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureStockholdersEquityStockGrantAgreementsWithNonEmployeesStockDetails" xlink:type="extended" xlink:title="40702 - Disclosure - STOCKHOLDERS' EQUITY - Stock grant agreements with non-employees, Stock (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityAbstract" xlink:label="us-gaap_EquityAbstract_636748512224559268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract_636748512224559268" xlink:to="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538747826" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="us-gaap_StatementEquityComponentsAxis_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538747826" xlink:to="us-gaap_StatementEquityComponentsAxis_637092576538747826" order="1" use="optional" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="us-gaap_EquityComponentDomain_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementEquityComponentsAxis_637092576538747826" xlink:to="us-gaap_EquityComponentDomain_637092576538747826" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockMember" xlink:label="us-gaap_CommonStockMember_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityComponentDomain_637092576538747826" xlink:to="us-gaap_CommonStockMember_637092576538747826" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusAxis" xlink:label="us-gaap_GranteeStatusAxis_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538747826" xlink:to="us-gaap_GranteeStatusAxis_637092576538747826" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusDomain" xlink:label="us-gaap_GranteeStatusDomain_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusAxis_637092576538747826" xlink:to="us-gaap_GranteeStatusDomain_637092576538747826" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedPaymentArrangementNonemployeeMember" xlink:label="us-gaap_ShareBasedPaymentArrangementNonemployeeMember_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusDomain_637092576538747826" xlink:to="us-gaap_ShareBasedPaymentArrangementNonemployeeMember_637092576538747826" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_TitleOfIndividualAxis" xlink:label="srt_TitleOfIndividualAxis_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538747826" xlink:to="srt_TitleOfIndividualAxis_637092576538747826" order="3" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="srt_TitleOfIndividualWithRelationshipToEntityDomain_637092576538747826" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_TitleOfIndividualAxis_637092576538747826" xlink:to="srt_TitleOfIndividualWithRelationshipToEntityDomain_637092576538747826" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ResearchersEmployeesOfMskMember" xlink:label="ymab_ResearchersEmployeesOfMskMember_637092576538757832" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_TitleOfIndividualWithRelationshipToEntityDomain_637092576538747826" xlink:to="ymab_ResearchersEmployeesOfMskMember_637092576538757832" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_IndividualWithStockGrantAgreementIpoMember" xlink:label="ymab_IndividualWithStockGrantAgreementIpoMember_637092576538757832" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_TitleOfIndividualWithRelationshipToEntityDomain_637092576538747826" xlink:to="ymab_IndividualWithStockGrantAgreementIpoMember_637092576538757832" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_StatementScenarioAxis" xlink:label="srt_StatementScenarioAxis_637092576538757832" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538747826" xlink:to="srt_StatementScenarioAxis_637092576538757832" order="4" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ScenarioUnspecifiedDomain" xlink:label="srt_ScenarioUnspecifiedDomain_637092576538757832" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_StatementScenarioAxis_637092576538757832" xlink:to="srt_ScenarioUnspecifiedDomain_637092576538757832" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ScenarioForecastMember" xlink:label="srt_ScenarioForecastMember_637092576538757832" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_ScenarioUnspecifiedDomain_637092576538757832" xlink:to="srt_ScenarioForecastMember_637092576538757832" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538757832" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538747826" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538757832" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_StockGrantAgreementsTotalSharesAgreedToBeIssued" xlink:label="ymab_StockGrantAgreementsTotalSharesAgreedToBeIssued_637092576538757832" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538757832" xlink:to="ymab_StockGrantAgreementsTotalSharesAgreedToBeIssued_637092576538757832" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_NumberOfIndividuals" xlink:label="ymab_NumberOfIndividuals_637092576538767879" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538757832" xlink:to="ymab_NumberOfIndividuals_637092576538767879" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesIssuedForServices" xlink:label="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_637092576538767879" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538757832" xlink:to="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_637092576538767879" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodShares" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538757832" xlink:to="us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_637092576538777904" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_EstimatedFairValueOfStockRepurchasedAndRetired" xlink:label="ymab_EstimatedFairValueOfStockRepurchasedAndRetired_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538757832" xlink:to="ymab_EstimatedFairValueOfStockRepurchasedAndRetired_637092576538777904" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodValue" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538757832" xlink:to="us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_637092576538777904" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureStockholdersEquityStockGrantAgreementsWithNonEmployeesStockOptionsDetails" xlink:type="extended" xlink:title="40703 - Disclosure - STOCKHOLDERS' EQUITY - Stock grant agreements with non employees, Stock options (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityAbstract" xlink:label="us-gaap_EquityAbstract_636771933347664232" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract_636771933347664232" xlink:to="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538777904" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="us-gaap_PlanNameAxis_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538777904" xlink:to="us-gaap_PlanNameAxis_637092576538777904" order="1" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="us-gaap_PlanNameDomain_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_PlanNameAxis_637092576538777904" xlink:to="us-gaap_PlanNameDomain_637092576538777904" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_EquityIncentivePlan2015Member" xlink:label="ymab_EquityIncentivePlan2015Member_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_PlanNameDomain_637092576538777904" xlink:to="ymab_EquityIncentivePlan2015Member_637092576538777904" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="us-gaap_AwardTypeAxis_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538777904" xlink:to="us-gaap_AwardTypeAxis_637092576538777904" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AwardTypeAxis_637092576538777904" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538777904" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="us-gaap_EmployeeStockOptionMember_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538777904" xlink:to="us-gaap_EmployeeStockOptionMember_637092576538777904" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusAxis" xlink:label="us-gaap_GranteeStatusAxis_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538777904" xlink:to="us-gaap_GranteeStatusAxis_637092576538777904" order="3" use="optional" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusDomain" xlink:label="us-gaap_GranteeStatusDomain_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusAxis_637092576538777904" xlink:to="us-gaap_GranteeStatusDomain_637092576538777904" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedPaymentArrangementNonemployeeMember" xlink:label="us-gaap_ShareBasedPaymentArrangementNonemployeeMember_637092576538777904" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusDomain_637092576538777904" xlink:to="us-gaap_ShareBasedPaymentArrangementNonemployeeMember_637092576538777904" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_VestingAxis" xlink:label="us-gaap_VestingAxis_637092576538787914" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538777904" xlink:to="us-gaap_VestingAxis_637092576538787914" order="4" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_VestingDomain" xlink:label="us-gaap_VestingDomain_637092576538787914" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_VestingAxis_637092576538787914" xlink:to="us-gaap_VestingDomain_637092576538787914" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationAwardTrancheOneMember" xlink:label="us-gaap_ShareBasedCompensationAwardTrancheOneMember_637092576538787914" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_VestingDomain_637092576538787914" xlink:to="us-gaap_ShareBasedCompensationAwardTrancheOneMember_637092576538787914" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationAwardTrancheTwoMember" xlink:label="us-gaap_ShareBasedCompensationAwardTrancheTwoMember_637092576538787914" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_VestingDomain_637092576538787914" xlink:to="us-gaap_ShareBasedCompensationAwardTrancheTwoMember_637092576538787914" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538787914" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538777904" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538787914" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_637092576538787914" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538787914" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_637092576538787914" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_NumberOfIndividuals" xlink:label="ymab_NumberOfIndividuals_637092576538787914" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538787914" xlink:to="ymab_NumberOfIndividuals_637092576538787914" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_637092576538787914" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538787914" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_637092576538787914" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_637092576538787914" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538787914" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_637092576538787914" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_637092576538797946" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538787914" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_637092576538797946" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureStockholdersEquityIssuanceOfCommonStockIpoDetails" xlink:type="extended" xlink:title="40704 - Disclosure - STOCKHOLDERS' EQUITY - Issuance of common stock, IPO (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityAbstract" xlink:label="us-gaap_EquityAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable" xlink:label="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_637092576538797946" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract" xlink:to="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_637092576538797946" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="us-gaap_StatementEquityComponentsAxis_637092576538797946" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_637092576538797946" xlink:to="us-gaap_StatementEquityComponentsAxis_637092576538797946" order="1" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="us-gaap_EquityComponentDomain_637092576538797946" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementEquityComponentsAxis_637092576538797946" xlink:to="us-gaap_EquityComponentDomain_637092576538797946" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockMember" xlink:label="us-gaap_CommonStockMember_637092576538807971" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityComponentDomain_637092576538797946" xlink:to="us-gaap_CommonStockMember_637092576538807971" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_637092576538807971" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_637092576538797946" xlink:to="us-gaap_SubsidiarySaleOfStockAxis_637092576538807971" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_637092576538807971" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiarySaleOfStockAxis_637092576538807971" xlink:to="us-gaap_SaleOfStockNameOfTransactionDomain_637092576538807971" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IPOMember" xlink:label="us-gaap_IPOMember_637092576538807971" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SaleOfStockNameOfTransactionDomain_637092576538807971" xlink:to="us-gaap_IPOMember_637092576538807971" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsidiarySaleOfStockLineItems" xlink:label="us-gaap_SubsidiarySaleOfStockLineItems_637092576538807971" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_637092576538797946" xlink:to="us-gaap_SubsidiarySaleOfStockLineItems_637092576538807971" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_637092576538807971" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiarySaleOfStockLineItems_637092576538807971" xlink:to="us-gaap_StockIssuedDuringPeriodSharesNewIssues_637092576538807971" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="7" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="us-gaap_SharesIssuedPricePerShare_637092576538807971" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiarySaleOfStockLineItems_637092576538807971" xlink:to="us-gaap_SharesIssuedPricePerShare_637092576538807971" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_637092576538807971" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiarySaleOfStockLineItems_637092576538807971" xlink:to="us-gaap_ProceedsFromIssuanceOfCommonStock_637092576538807971" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="5" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureStockholdersEquityIssuanceOfCommonStockStockGrantAgreementsDetails" xlink:type="extended" xlink:title="40705 - Disclosure - STOCKHOLDERS' EQUITY - Issuance of common stock, Stock grant agreements (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityAbstract" xlink:label="us-gaap_EquityAbstract_637006952150095021" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityAbstract_637006952150095021" xlink:to="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="us-gaap_StatementEquityComponentsAxis_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" xlink:to="us-gaap_StatementEquityComponentsAxis_637092576538817988" order="1" use="optional" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="us-gaap_EquityComponentDomain_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_StatementEquityComponentsAxis_637092576538817988" xlink:to="us-gaap_EquityComponentDomain_637092576538817988" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockMember" xlink:label="us-gaap_CommonStockMember_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EquityComponentDomain_637092576538817988" xlink:to="us-gaap_CommonStockMember_637092576538817988" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusAxis" xlink:label="us-gaap_GranteeStatusAxis_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" xlink:to="us-gaap_GranteeStatusAxis_637092576538817988" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusDomain" xlink:label="us-gaap_GranteeStatusDomain_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusAxis_637092576538817988" xlink:to="us-gaap_GranteeStatusDomain_637092576538817988" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedPaymentArrangementNonemployeeMember" xlink:label="us-gaap_ShareBasedPaymentArrangementNonemployeeMember_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusDomain_637092576538817988" xlink:to="us-gaap_ShareBasedPaymentArrangementNonemployeeMember_637092576538817988" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_TitleOfIndividualAxis" xlink:label="srt_TitleOfIndividualAxis_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" xlink:to="srt_TitleOfIndividualAxis_637092576538817988" order="3" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="srt_TitleOfIndividualWithRelationshipToEntityDomain_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_TitleOfIndividualAxis_637092576538817988" xlink:to="srt_TitleOfIndividualWithRelationshipToEntityDomain_637092576538817988" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_IndividualWithStockGrantAgreementIpoMember" xlink:label="ymab_IndividualWithStockGrantAgreementIpoMember_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_TitleOfIndividualWithRelationshipToEntityDomain_637092576538817988" xlink:to="ymab_IndividualWithStockGrantAgreementIpoMember_637092576538817988" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ResearchersEmployeesOfMskMember" xlink:label="ymab_ResearchersEmployeesOfMskMember_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_TitleOfIndividualWithRelationshipToEntityDomain_637092576538817988" xlink:to="ymab_ResearchersEmployeesOfMskMember_637092576538817988" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538817988" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesIssuedForServices" xlink:label="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538817988" xlink:to="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_637092576538817988" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureShareBasedCompensation2015PlanDetails" xlink:type="extended" xlink:title="40801 - Disclosure - SHARE-BASED COMPENSATION - 2015 Plan (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_636992259763494257" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_636992259763494257" xlink:to="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="us-gaap_PlanNameAxis_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" xlink:to="us-gaap_PlanNameAxis_637092576538828039" order="1" use="optional" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="us-gaap_PlanNameDomain_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_PlanNameAxis_637092576538828039" xlink:to="us-gaap_PlanNameDomain_637092576538828039" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_EquityIncentivePlan2015Member" xlink:label="ymab_EquityIncentivePlan2015Member_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_PlanNameDomain_637092576538828039" xlink:to="ymab_EquityIncentivePlan2015Member_637092576538828039" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="us-gaap_AwardTypeAxis_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" xlink:to="us-gaap_AwardTypeAxis_637092576538828039" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AwardTypeAxis_637092576538828039" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538828039" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="us-gaap_EmployeeStockOptionMember_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538828039" xlink:to="us-gaap_EmployeeStockOptionMember_637092576538828039" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusAxis" xlink:label="us-gaap_GranteeStatusAxis_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" xlink:to="us-gaap_GranteeStatusAxis_637092576538828039" order="3" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusDomain" xlink:label="us-gaap_GranteeStatusDomain_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusAxis_637092576538828039" xlink:to="us-gaap_GranteeStatusDomain_637092576538828039" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember" xlink:label="ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusDomain_637092576538828039" xlink:to="ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember_637092576538828039" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538817988" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538828039" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538828039" xlink:to="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_637092576538828039" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538828039" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_637092576538828039" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538828039" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_637092576538828039" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureShareBasedCompensation2018PlanDetails" xlink:type="extended" xlink:title="40802 - Disclosure - SHARE-BASED COMPENSATION - 2018 Plan (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_636776293047726896" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_636776293047726896" xlink:to="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538828039" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="us-gaap_PlanNameAxis_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538828039" xlink:to="us-gaap_PlanNameAxis_637092576538828039" order="1" use="optional" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="us-gaap_PlanNameDomain_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_PlanNameAxis_637092576538828039" xlink:to="us-gaap_PlanNameDomain_637092576538828039" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_EquityIncentivePlan2018Member" xlink:label="ymab_EquityIncentivePlan2018Member_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_PlanNameDomain_637092576538828039" xlink:to="ymab_EquityIncentivePlan2018Member_637092576538828039" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="us-gaap_AwardTypeAxis_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538828039" xlink:to="us-gaap_AwardTypeAxis_637092576538828039" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AwardTypeAxis_637092576538828039" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538828039" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="us-gaap_EmployeeStockOptionMember_637092576538828039" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538828039" xlink:to="us-gaap_EmployeeStockOptionMember_637092576538828039" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusAxis" xlink:label="us-gaap_GranteeStatusAxis_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538828039" xlink:to="us-gaap_GranteeStatusAxis_637092576538838067" order="3" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusDomain" xlink:label="us-gaap_GranteeStatusDomain_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusAxis_637092576538838067" xlink:to="us-gaap_GranteeStatusDomain_637092576538838067" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember" xlink:label="ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusDomain_637092576538838067" xlink:to="ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember_637092576538838067" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_GranteeOwningMoreThanTenPercentOfVotingPowerMember" xlink:label="ymab_GranteeOwningMoreThanTenPercentOfVotingPowerMember_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusDomain_637092576538838067" xlink:to="ymab_GranteeOwningMoreThanTenPercentOfVotingPowerMember_637092576538838067" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeAxis" xlink:label="srt_RangeAxis_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538828039" xlink:to="srt_RangeAxis_637092576538838067" order="4" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeMember" xlink:label="srt_RangeMember_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_RangeAxis_637092576538838067" xlink:to="srt_RangeMember_637092576538838067" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_MinimumMember" xlink:label="srt_MinimumMember_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="srt_RangeMember_637092576538838067" xlink:to="srt_MinimumMember_637092576538838067" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538828039" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538838067" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538838067" xlink:to="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_637092576538838067" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538838067" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum_637092576538838067" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538838067" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_637092576538838067" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_OwnershipVotingPower" xlink:label="ymab_OwnershipVotingPower_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538838067" xlink:to="ymab_OwnershipVotingPower_637092576538838067" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_OptionPriceAsPercentageOfFairMarketValueOfCommonStockOnGrantDate" xlink:label="ymab_OptionPriceAsPercentageOfFairMarketValueOfCommonStockOnGrantDate_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538838067" xlink:to="ymab_OptionPriceAsPercentageOfFairMarketValueOfCommonStockOnGrantDate_637092576538838067" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538838067" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_637092576538838067" order="6" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_637092576538838067" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538838067" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_637092576538838067" order="7" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureShareBasedCompensationExpenseDetails" xlink:type="extended" xlink:title="40803 - Disclosure - SHARE-BASED COMPENSATION - Expense (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_636748512224559268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_636748512224559268" xlink:to="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538848088" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="us-gaap_AwardTypeAxis_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538848088" xlink:to="us-gaap_AwardTypeAxis_637092576538848088" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AwardTypeAxis_637092576538848088" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538848088" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="us-gaap_EmployeeStockOptionMember_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538848088" xlink:to="us-gaap_EmployeeStockOptionMember_637092576538848088" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusAxis" xlink:label="us-gaap_GranteeStatusAxis_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538848088" xlink:to="us-gaap_GranteeStatusAxis_637092576538848088" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusDomain" xlink:label="us-gaap_GranteeStatusDomain_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusAxis_637092576538848088" xlink:to="us-gaap_GranteeStatusDomain_637092576538848088" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember" xlink:label="ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusDomain_637092576538848088" xlink:to="ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember_637092576538848088" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_EmployeesAndDirectorsMember" xlink:label="ymab_EmployeesAndDirectorsMember_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember_637092576538848088" xlink:to="ymab_EmployeesAndDirectorsMember_637092576538848088" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_EmployeesNonEmployeesAndDirectorsMember" xlink:label="ymab_EmployeesNonEmployeesAndDirectorsMember_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember_637092576538848088" xlink:to="ymab_EmployeesNonEmployeesAndDirectorsMember_637092576538848088" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedPaymentArrangementNonemployeeMember" xlink:label="us-gaap_ShareBasedPaymentArrangementNonemployeeMember_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_ShareBasedPaymentArrangementEmployeeAndNonemployeeMember_637092576538848088" xlink:to="us-gaap_ShareBasedPaymentArrangementNonemployeeMember_637092576538848088" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="us-gaap_IncomeStatementLocationAxis_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538848088" xlink:to="us-gaap_IncomeStatementLocationAxis_637092576538848088" order="3" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="us-gaap_IncomeStatementLocationDomain_637092576538848088" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeStatementLocationAxis_637092576538848088" xlink:to="us-gaap_IncomeStatementLocationDomain_637092576538848088" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ResearchAndDevelopmentExpenseMember" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_637092576538858110" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeStatementLocationDomain_637092576538848088" xlink:to="us-gaap_ResearchAndDevelopmentExpenseMember_637092576538858110" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GeneralAndAdministrativeExpenseMember" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_637092576538858110" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeStatementLocationDomain_637092576538848088" xlink:to="us-gaap_GeneralAndAdministrativeExpenseMember_637092576538858110" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538858110" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538848088" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538858110" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_637092576538858110" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538858110" xlink:to="us-gaap_AllocatedShareBasedCompensationExpense_637092576538858110" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="3" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureShareBasedCompensationStockOptionsDetails" xlink:type="extended" xlink:title="40804 - Disclosure - SHARE-BASED COMPENSATION - Stock options (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_637092576538858110" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_637092576538858110" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_637092576538858110" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_637092576538858110" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_637092576538858110" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_637092576538858110" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_637092576538858110" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_637092576538858110" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_6370925765388581101" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_637092576538858110" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_6370925765388581101" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_637092576538868160" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_637092576538858110" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_637092576538868160" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_637092576538868160" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_637092576538868160" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_637092576538868160" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_637092576538868160" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_637092576538868160" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_637092576538868160" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_637092576538868160" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_637092576538868160" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_6370925765388681601" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_637092576538868160" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_6370925765388681601" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_637092576538868160" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_637092576538868160" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_637092576538868160" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="8" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_637092576538868160" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_637092576538868160" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_637092576538868160" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_637092576538868160" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_637092576538868160" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_637092576538868160" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_637092576538868160" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_637092576538868160" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="9" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_637092576538868160" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_637092576538868160" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_637092576538868160" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="8" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_637092576538868160" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_637092576538868160" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_637092576538868160" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_637092576538868160" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_637092576538868160" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_637092576538868160" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureShareBasedCompensationUnrecognizedCompensationDetails" xlink:type="extended" xlink:title="40805 - Disclosure - SHARE-BASED COMPENSATION - Unrecognized compensation (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538878181" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:to="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538878181" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="us-gaap_AwardTypeAxis_637092576538878181" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538878181" xlink:to="us-gaap_AwardTypeAxis_637092576538878181" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538878181" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AwardTypeAxis_637092576538878181" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538878181" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="us-gaap_EmployeeStockOptionMember_637092576538878181" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538878181" xlink:to="us-gaap_EmployeeStockOptionMember_637092576538878181" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusAxis" xlink:label="us-gaap_GranteeStatusAxis_637092576538878181" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538878181" xlink:to="us-gaap_GranteeStatusAxis_637092576538878181" order="2" use="optional" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GranteeStatusDomain" xlink:label="us-gaap_GranteeStatusDomain_637092576538888177" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusAxis_637092576538878181" xlink:to="us-gaap_GranteeStatusDomain_637092576538888177" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedPaymentArrangementEmployeeMember" xlink:label="us-gaap_ShareBasedPaymentArrangementEmployeeMember_637092576538888177" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_GranteeStatusDomain_637092576538888177" xlink:to="us-gaap_ShareBasedPaymentArrangementEmployeeMember_637092576538888177" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538888177" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538878181" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538888177" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedAbstract" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedAbstract_637092576538888177" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538888177" xlink:to="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedAbstract_637092576538888177" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_637092576538888177" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedAbstract_637092576538888177" xlink:to="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_637092576538888177" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_637092576538888177" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedAbstract_637092576538888177" xlink:to="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_637092576538888177" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureShareBasedCompensationRestrictedStockUnitActivityDetails" xlink:type="extended" xlink:title="40806 - Disclosure - SHARE-BASED COMPENSATION - Restricted Stock Unit Activity (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_636929313525954101" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_636929313525954101" xlink:to="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538898209" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="us-gaap_AwardTypeAxis_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538898209" xlink:to="us-gaap_AwardTypeAxis_637092576538898209" order="1" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_AwardTypeAxis_637092576538898209" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538898209" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_637092576538898209" xlink:to="us-gaap_RestrictedStockUnitsRSUMember_637092576538898209" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="us-gaap_IncomeStatementLocationAxis_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538898209" xlink:to="us-gaap_IncomeStatementLocationAxis_637092576538898209" order="2" use="optional" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="us-gaap_IncomeStatementLocationDomain_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeStatementLocationAxis_637092576538898209" xlink:to="us-gaap_IncomeStatementLocationDomain_637092576538898209" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ResearchAndDevelopmentExpenseMember" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeStatementLocationDomain_637092576538898209" xlink:to="us-gaap_ResearchAndDevelopmentExpenseMember_637092576538898209" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GeneralAndAdministrativeExpenseMember" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeStatementLocationDomain_637092576538898209" xlink:to="us-gaap_GeneralAndAdministrativeExpenseMember_637092576538898209" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_637092576538898209" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538898209" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538898209" xlink:to="us-gaap_AllocatedShareBasedCompensationExpense_637092576538898209" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538898209" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_637092576538898209" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_637092576538898209" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_637092576538898209" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_637092576538898209" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_637092576538898209" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_6370925765388982091" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_637092576538898209" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_6370925765388982091" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538898209" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_637092576538898209" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538898209" xlink:to="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_637092576538898209" order="4" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_637092576538898209" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_637092576538898209" xlink:to="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_637092576538898209" order="5" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="4" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureRelatedPartyTransactionsDetails" xlink:type="extended" xlink:title="40901 - Disclosure - RELATED PARTY TRANSACTIONS (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RelatedPartyTransactionsAbstract" xlink:label="us-gaap_RelatedPartyTransactionsAbstract_636748512807219268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:label="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_RelatedPartyTransactionsAbstract_636748512807219268" xlink:to="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_637092576538908256" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_637092576538908256" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_637092576538908256" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RelatedPartyDomain" xlink:label="us-gaap_RelatedPartyDomain_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_637092576538908256" xlink:to="us-gaap_RelatedPartyDomain_637092576538908256" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_ShareholderMskMember" xlink:label="ymab_ShareholderMskMember_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_RelatedPartyDomain_637092576538908256" xlink:to="ymab_ShareholderMskMember_637092576538908256" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="us-gaap_RelatedPartyTransactionAxis_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_637092576538908256" xlink:to="us-gaap_RelatedPartyTransactionAxis_637092576538908256" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="us-gaap_RelatedPartyTransactionDomain_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_RelatedPartyTransactionAxis_637092576538908256" xlink:to="us-gaap_RelatedPartyTransactionDomain_637092576538908256" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LicenseAndOtherAgreementsMember" xlink:label="ymab_LicenseAndOtherAgreementsMember_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_RelatedPartyTransactionDomain_637092576538908256" xlink:to="ymab_LicenseAndOtherAgreementsMember_637092576538908256" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RelatedPartyTransactionLineItems" xlink:label="us-gaap_RelatedPartyTransactionLineItems_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_637092576538908256" xlink:to="us-gaap_RelatedPartyTransactionLineItems_637092576538908256" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty" xlink:label="us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_RelatedPartyTransactionLineItems_637092576538908256" xlink:to="us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty_637092576538908256" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="5" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DueToRelatedPartiesCurrentAndNoncurrent" xlink:label="us-gaap_DueToRelatedPartiesCurrentAndNoncurrent_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_RelatedPartyTransactionLineItems_637092576538908256" xlink:to="us-gaap_DueToRelatedPartiesCurrentAndNoncurrent_637092576538908256" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_LeasePayablePerMonth" xlink:label="ymab_LeasePayablePerMonth_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_RelatedPartyTransactionLineItems_637092576538908256" xlink:to="ymab_LeasePayablePerMonth_637092576538908256" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="1" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureIncomeTaxesExpenseDetails" xlink:type="extended" xlink:title="41001 - Disclosure - INCOME TAXES - Expense (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_636748512807219268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract" xlink:label="us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeTaxDisclosureAbstract_636748512807219268" xlink:to="us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_637092576538908256" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CurrentIncomeTaxExpenseBenefit" xlink:label="us-gaap_CurrentIncomeTaxExpenseBenefit_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_637092576538908256" xlink:to="us-gaap_CurrentIncomeTaxExpenseBenefit_637092576538908256" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_637092576538908256" xlink:to="us-gaap_DeferredIncomeTaxExpenseBenefit_637092576538908256" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_637092576538908256" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_637092576538908256" xlink:to="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_637092576538908256" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="6" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureIncomeTaxesUncertainTaxPositionsDetails" xlink:type="extended" xlink:title="41002 - Disclosure - INCOME TAXES - Uncertain tax positions (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_636765795167565020" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_UnrecognizedTaxBenefits" xlink:label="us-gaap_UnrecognizedTaxBenefits_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_IncomeTaxDisclosureAbstract_636765795167565020" xlink:to="us-gaap_UnrecognizedTaxBenefits_637092576538918280" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="5" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureOtherBenefitsDetails" xlink:type="extended" xlink:title="41101 - Disclosure - OTHER BENEFITS (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_OtherBenefitsDisclosureAbstract" xlink:label="ymab_OtherBenefitsDisclosureAbstract" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:label="us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="ymab_OtherBenefitsDisclosureAbstract" xlink:to="us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent_637092576538918280" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" />
  </presentationLink>
  <presentationLink xlink:role="http://www.ymabs.com/role/DisclosureSubsequentEventsDetails" xlink:type="extended" xlink:title="41201 - Disclosure - SUBSEQUENT EVENTS (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="us-gaap_SubsequentEventsAbstract_636748512807219268" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTable" xlink:label="us-gaap_SubsequentEventTable_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventsAbstract_636748512807219268" xlink:to="us-gaap_SubsequentEventTable_637092576538918280" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="us-gaap_SubsequentEventTypeAxis_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventTable_637092576538918280" xlink:to="us-gaap_SubsequentEventTypeAxis_637092576538918280" order="1" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="us-gaap_SubsequentEventTypeDomain_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventTypeAxis_637092576538918280" xlink:to="us-gaap_SubsequentEventTypeDomain_637092576538918280" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="us-gaap_SubsequentEventMember_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventTypeDomain_637092576538918280" xlink:to="us-gaap_SubsequentEventMember_637092576538918280" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventTable_637092576538918280" xlink:to="us-gaap_SubsidiarySaleOfStockAxis_637092576538918280" order="2" use="optional" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsidiarySaleOfStockAxis_637092576538918280" xlink:to="us-gaap_SaleOfStockNameOfTransactionDomain_637092576538918280" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="ymab-20190930.xsd#ymab_FollowOnShelfPublicOfferingMember" xlink:label="ymab_FollowOnShelfPublicOfferingMember_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SaleOfStockNameOfTransactionDomain_637092576538918280" xlink:to="ymab_FollowOnShelfPublicOfferingMember_637092576538918280" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventLineItems" xlink:label="us-gaap_SubsequentEventLineItems_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventTable_637092576538918280" xlink:to="us-gaap_SubsequentEventLineItems_637092576538918280" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventLineItems_637092576538918280" xlink:to="us-gaap_StockIssuedDuringPeriodSharesNewIssues_637092576538918280" order="1" use="optional" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="us-gaap_SharesIssuedPricePerShare_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventLineItems_637092576538918280" xlink:to="us-gaap_SharesIssuedPricePerShare_637092576538918280" order="2" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_637092576538918280" />
    <presentationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="us-gaap_SubsequentEventLineItems_637092576538918280" xlink:to="us-gaap_ProceedsFromIssuanceOfCommonStock_637092576538918280" order="3" use="optional" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="4" />
  </presentationLink>
</link:linkbase>
