<?xml version="1.0"?><ownershipDocument><schemaVersion>X0201</schemaVersion>    <documentType>4</documentType><periodOfReport>2003-11-21</periodOfReport><notSubjectToSection16>0</notSubjectToSection16><issuer><issuerCik>0000320345</issuerCik><issuerName>MICROS SYSTEMS INC</issuerName>        <issuerTradingSymbol>MCRS</issuerTradingSymbol></issuer><reportingOwner><reportingOwnerId><rptOwnerCik>0001246456</rptOwnerCik><rptOwnerName>INTERLANDI DANIEL G</rptOwnerName></reportingOwnerId><reportingOwnerAddress><rptOwnerStreet1>7031 COLUMBIA GATEWAY DRIVE</rptOwnerStreet1><rptOwnerStreet2></rptOwnerStreet2><rptOwnerCity>COLUMBIA</rptOwnerCity><rptOwnerState>MD</rptOwnerState><rptOwnerZipCode>21046-2289</rptOwnerZipCode><rptOwnerStateDescription></rptOwnerStateDescription></reportingOwnerAddress><reportingOwnerRelationship><isDirector>0</isDirector><isOfficer>1</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther><officerTitle>EVP, Americas Group</officerTitle></reportingOwnerRelationship></reportingOwner><derivativeTable><derivativeTransaction><securityTitle><value>Incentive Stock Option (right to buy)</value></securityTitle><conversionOrExercisePrice><value>42.0750</value></conversionOrExercisePrice><transactionDate><value>2003-11-21</value></transactionDate><deemedExecutionDate></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>A</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>4752.0000</value></transactionShares><transactionPricePerShare><value>42.0750</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><value>2004-11-21</value><footnoteId id="F1" /></exerciseDate><expirationDate><value>2013-11-21</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>4752.0000</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>4752.0000</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeTransaction><derivativeTransaction><securityTitle><value>Non-Qualified Stock Option (right to buy)</value></securityTitle><conversionOrExercisePrice><value>42.0750</value></conversionOrExercisePrice><transactionDate><value>2003-11-21</value></transactionDate><deemedExecutionDate></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>A</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>25248.0000</value></transactionShares><transactionPricePerShare><value>42.0750</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><value>2004-11-21</value><footnoteId id="F1" /></exerciseDate><expirationDate><value>2013-11-21</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>25248.0000</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>25248.0000</value><footnoteId id="F2" /></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeTransaction></derivativeTable><footnotes><footnote id="F1">First one-third exercisable one year after date of grant; second one-third exercisable two years after date of grant; final one-third exercisable three years after date of grant.</footnote><footnote id="F2">Daniel G. Interlandi owns derivative securities in the form of non-qualified stock options and incentive stock options in the aggregate amount of 241,030 shares.</footnote></footnotes><remarks></remarks><ownerSignature><signatureName>Thomas L. Patz for Daniel G. Interlandi</signatureName><signatureDate>2003-11-25</signatureDate></ownerSignature></ownershipDocument>

