<?xml version="1.0"?><ownershipDocument><schemaVersion>X0201</schemaVersion>    <documentType>4</documentType><periodOfReport>2004-01-15</periodOfReport><notSubjectToSection16>0</notSubjectToSection16><issuer><issuerCik>0000799166</issuerCik><issuerName>MASSBANK CORP</issuerName>        <issuerTradingSymbol>MASB</issuerTradingSymbol></issuer><reportingOwner><reportingOwnerId><rptOwnerCik>0001235371</rptOwnerCik><rptOwnerName>CORMIER REGINALD E</rptOwnerName></reportingOwnerId><reportingOwnerAddress><rptOwnerStreet1>C/O MASSBANK CORP</rptOwnerStreet1><rptOwnerStreet2>123 HAVEN STREET</rptOwnerStreet2><rptOwnerCity>READING</rptOwnerCity><rptOwnerState>MA</rptOwnerState><rptOwnerZipCode>01867</rptOwnerZipCode><rptOwnerStateDescription></rptOwnerStateDescription></reportingOwnerAddress><reportingOwnerRelationship><isDirector>0</isDirector><isOfficer>1</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther><officerTitle>SVP, Treasurer &amp; CFO</officerTitle></reportingOwnerRelationship></reportingOwner><derivativeTable><derivativeTransaction><securityTitle><value>Option(Right to buy)</value></securityTitle><conversionOrExercisePrice><value>42.9000</value></conversionOrExercisePrice><transactionDate><value>2004-01-15</value></transactionDate><deemedExecutionDate></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>J</transactionCode><equitySwapInvolved>0</equitySwapInvolved><footnoteId id="F1" /></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>2500.0000</value></transactionShares><transactionPricePerShare><value>42.9000</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><value>2004-01-15</value></exerciseDate><expirationDate><value>2014-01-14</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common</value></underlyingSecurityTitle><underlyingSecurityShares><value>2500.0000</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>2500.0000</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeTransaction></derivativeTable><footnotes><footnote id="F1">Grant of Stock Option under the MASSBANK Corp 1994 Stock Incentive Plan</footnote></footnotes><remarks></remarks><ownerSignature><signatureName>Reginald E. Cormier</signatureName><signatureDate>2004-01-20</signatureDate></ownerSignature></ownershipDocument>

