<?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>0001235387</rptOwnerCik><rptOwnerName>QUEENEY THOMAS J</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>0</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>1</isOther><otherText>VP, Sr Trust Officer, MASSBANK</otherText></reportingOwnerRelationship></reportingOwner><nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock MASSBANK Corp</value></securityTitle><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>1000.0000</value></transactionShares><transactionPricePerShare><value>11.5625</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>9105.9494</value><footnoteId id="F2" /></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></nonDerivativeTransaction></nonDerivativeTable><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="F3" /></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>2000.0000</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>2000.0000</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>2000.0000</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeTransaction><derivativeTransaction><securityTitle><value>Option(Right to buy)</value></securityTitle><conversionOrExercisePrice><value>11.5625</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>1000.0000</value></transactionShares><transactionPricePerShare><value>11.5625</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><value>1995-01-17</value></exerciseDate><expirationDate><value>2005-01-16</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common</value></underlyingSecurityTitle><underlyingSecurityShares><value>1000.0000</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>0</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeTransaction></derivativeTable><footnotes><footnote id="F1">Exercise of stock option granted under the MASSBANK Corp 1986 Stock Option Plan</footnote><footnote id="F2">Includes 4,000.000 shares owned directly by Mr.Queeney.  Also includes 5,105.9494 shares owned indirectly by Mr. Queeney under the MASSBANK Corp Employee Stock Ownership Plan (ESOP). </footnote><footnote id="F3">Stock Option granted under the MASSBANK Corp 1994 Stock Incentive Plan</footnote></footnotes><remarks></remarks><ownerSignature><signatureName>Thomas J. Queeney</signatureName><signatureDate>2004-01-20</signatureDate></ownerSignature></ownershipDocument>

