<?xml version="1.0"?>
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType><periodOfReport>2003-11-13</periodOfReport>
    <issuer>
        <issuerCik>0001097338</issuerCik>
        <issuerName>WITNESS SYSTEMS INC</issuerName>
        <issuerTradingSymbol>WITS</issuerTradingSymbol></issuer><reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001034707</rptOwnerCik>
            <rptOwnerName>BATTERY VENTURES IV LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O BATTERY VENTURES</rptOwnerStreet1>
            <rptOwnerStreet2>20 WILLIAM STREET, SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>WELLESLEY</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02481</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector><isOfficer>0</isOfficer><isTenPercentOwner>1</isTenPercentOwner><isOther>0</isOther></reportingOwnerRelationship></reportingOwner><nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-11-13</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>J</transactionCode><equitySwapInvolved>0</equitySwapInvolved><footnoteId id="F1"/></transactionCoding><transactionAmounts><transactionShares><value>1250000</value></transactionShares><transactionPricePerShare><footnoteId id="F3"/></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>2982197</value><footnoteId id="F4"/></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value><footnoteId id="F4"/></directOrIndirectOwnership><natureOfOwnership><value>See Footnote</value><footnoteId id="F6"/></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-11-13</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>J</transactionCode><equitySwapInvolved>0</equitySwapInvolved><footnoteId id="F2"/></transactionCoding><transactionAmounts><transactionShares><value>19035</value></transactionShares><transactionPricePerShare><footnoteId id="F3"/></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>2963162</value><footnoteId id="F5"/></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value><footnoteId id="F5"/></directOrIndirectOwnership><natureOfOwnership><value>See Footnote</value><footnoteId id="F6"/></natureOfOwnership></ownershipNature></nonDerivativeTransaction></nonDerivativeTable><footnotes><footnote id="F1">Distribution to the partners of Battery Ventures IV, L.P. (&quot;Battery Ventures&quot;) for no consideration.</footnote><footnote id="F2">Distribution to the members of Battery Investment Partners IV, LLC (&quot;BIP&quot;) for no consideration.</footnote><footnote id="F3">Not applicable</footnote><footnote id="F4">Includes 2,918,714 shares directly owned and 63,483 shares held of record by BIP.</footnote><footnote id="F5">Includes 2,918,714 shares held of record by Battery Ventures and 44,448 shares held of record by BIP.</footnote><footnote id="F6"> BIP invests alongside Battery Ventures in all investments made by Battery Ventures and, therefore, Battery Ventures may be deemed to beneficially own the shares held of record by BIP.  Battery Ventures disclaims beneficial ownership of the shares beneficially owned by BIP.  BIP disclaims beneficial ownership of the shares beneficially owned by Battery Ventures.</footnote></footnotes><remarks/><ownerSignature><signatureName>Battery Ventures IV, L.P., by Christopher Hanson as Attorney-in-Fact for Richard D. Frisbie, Member Manager of Battery Partners IV, LLC</signatureName><signatureDate>2003-11-17</signatureDate></ownerSignature></ownershipDocument>

