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  <xs:element id="alx_DeferredStockUnitsMember" abstract="true" name="DeferredStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_RegoPark1PropertyMember" abstract="true" name="RegoPark1PropertyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_ManagementFeeAgreementValue" abstract="false" name="ManagementFeeAgreementValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_AlexandersInc.Member" abstract="true" name="AlexandersInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_PercentageCommissionsOnSaleOfAssetsOverFiftyMillion" abstract="false" name="PercentageCommissionsOnSaleOfAssetsOverFiftyMillion" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="alx_TenantOccupantMember" abstract="true" name="TenantOccupantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_AllRiskPropertyAndRentalValueMember" abstract="true" name="AllRiskPropertyAndRentalValueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_SearsMember" abstract="true" name="SearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_FiftyNinthStreetInsuranceCompanyLlcMember" abstract="true" name="FiftyNinthStreetInsuranceCompanyLlcMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_BloombergMember" abstract="true" name="BloombergMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_LeasingFeesMember" abstract="true" name="LeasingFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_LexingtonAvenuePropertyMember" abstract="true" name="LexingtonAvenuePropertyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_LeaseFeePercentageOfRentTwentyFirstToThirtyYears" abstract="false" name="LeaseFeePercentageOfRentTwentyFirstToThirtyYears" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="alx_PaymentsForCapitalImprovementsAndConstructionInProcessAndOther" abstract="false" name="PaymentsForCapitalImprovementsAndConstructionInProcessAndOther" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_RegoPark2PropertyMember" abstract="true" name="RegoPark2PropertyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_ParticipationAgreementMember" abstract="true" name="ParticipationAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_NumberOfFires" abstract="false" name="NumberOfFires" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="alx_MacerichMember" abstract="true" name="MacerichMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_PropertyManagementFeeEscalationPercentagePerAnnum" abstract="false" name="PropertyManagementFeeEscalationPercentagePerAnnum" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="alx_ProceedsFromSaleOfLandHeldForInvestmentExcludingDisposalCost" abstract="false" name="ProceedsFromSaleOfLandHeldForInvestmentExcludingDisposalCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_InsuranceDeductible" abstract="false" name="InsuranceDeductible" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_NotesPayableGross" abstract="false" name="NotesPayableGross" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_IkeaMember" abstract="true" name="IkeaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_DevelopmentFeePercentage" abstract="false" name="DevelopmentFeePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="alx_VornadoMember" abstract="true" name="VornadoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_CommissionOnSaleOfRealEstateMember" abstract="true" name="CommissionOnSaleOfRealEstateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_DirectServicesMember" abstract="true" name="DirectServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_PropertyManagementFeeAgreementPricePerSquareFoot" abstract="false" name="PropertyManagementFeeAgreementPricePerSquareFoot" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="srt-types:perUnitItemType"/>
  <xs:element id="alx_EstimatedFutureDamagesMember" abstract="true" name="EstimatedFutureDamagesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_InsuranceMaximumCoveragePerIncident" abstract="false" name="InsuranceMaximumCoveragePerIncident" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_PropertyManagementFeeAgreementValue" abstract="false" name="PropertyManagementFeeAgreementValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_TerrorismCoverageIncludingNbcrMember" abstract="true" name="TerrorismCoverageIncludingNbcrMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_AssetSaleCommissionThreshold" abstract="false" name="AssetSaleCommissionThreshold" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_InsuranceMaximumCoveragePerProperty" abstract="false" name="InsuranceMaximumCoveragePerProperty" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_PropertyManagementFeesMember" abstract="true" name="PropertyManagementFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_OfficeAndRetailSpaceMember" abstract="true" name="OfficeAndRetailSpaceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_FederalGovernmentResponsibility" abstract="false" name="FederalGovernmentResponsibility" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="alx_WriteOffOfFullyAmortizedAndDepreciatedAssets" abstract="false" name="WriteOffOfFullyAmortizedAndDepreciatedAssets" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_NbcrMember" abstract="true" name="NbcrMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_ProceedsFromSaleOfLandHeldForInvestmentNet" abstract="false" name="ProceedsFromSaleOfLandHeldForInvestmentNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_PercentageCommissionsOnSaleOfAssetsUnderFiftyMillion" abstract="false" name="PercentageCommissionsOnSaleOfAssetsUnderFiftyMillion" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="alx_ScheduleOfInsuranceTypeAndTierIdentifierAxis" abstract="true" name="ScheduleOfInsuranceTypeAndTierIdentifierAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="alx_RealEstatePropertyOccupantAxis" abstract="true" name="RealEstatePropertyOccupantAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="alx_RealEstatePropertyOccupantDomain" abstract="true" name="RealEstatePropertyOccupantDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsMarketValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsMarketValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_CompanyManagementFeesMember" abstract="true" name="CompanyManagementFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_ManagementPropertyManagementCleaningEngineeringAndSecurityFeesMember" abstract="true" name="ManagementPropertyManagementCleaningEngineeringAndSecurityFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_DiseaseCoverageMember" abstract="true" name="DiseaseCoverageMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_InsuranceMaximumCoverageInAggregate" abstract="false" name="InsuranceMaximumCoverageInAggregate" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_BronxLandParcelMember" abstract="true" name="BronxLandParcelMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_LeaseFeePercentageOfRentOneToTenYears" abstract="false" name="LeaseFeePercentageOfRentOneToTenYears" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="alx_TypesAndTierIdentifierDomain" abstract="true" name="TypesAndTierIdentifierDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_UnamortizedLeasingFeesToRelatedParty" abstract="false" name="UnamortizedLeasingFeesToRelatedParty" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="alx_PercentageIncreaseLeaseFeeIfBrokerUsed" abstract="false" name="PercentageIncreaseLeaseFeeIfBrokerUsed" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="alx_A2016OmnibusStockPlanMember" abstract="true" name="A2016OmnibusStockPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="alx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGrantedPerDirector" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGrantedPerDirector" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="alx_SelfInsuredResponsibility" abstract="false" name="SelfInsuredResponsibility" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="alx_CommonAreaMember" abstract="true" name="CommonAreaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
