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

    <documentType>4</documentType><periodOfReport>2003-10-23</periodOfReport>
    <issuer>
        <issuerCik>0000912603</issuerCik>
        <issuerName>SCHNITZER STEEL INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>SCHN</issuerTradingSymbol></issuer><reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001249487</rptOwnerCik>
            <rptOwnerName>EDELSON JILL SCHNITZER</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3200 NW YEON AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PORTLAND</rptOwnerCity>
            <rptOwnerState>OR</rptOwnerState>
            <rptOwnerZipCode>97210</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector><isOfficer>0</isOfficer><isTenPercentOwner>1</isTenPercentOwner><isOther>0</isOther></reportingOwnerRelationship></reportingOwner><nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Class A Common Stock</value></securityTitle><transactionDate><value>2003-10-23</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>3932</value></transactionShares><transactionPricePerShare><value>35.4103</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>0</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>By Trust</value><footnoteId id="F1"/></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Class A Common Stock</value></securityTitle><transactionDate><value>2003-10-24</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>C</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>20000</value></transactionShares><transactionPricePerShare><value>0</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>20000</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>By Voting Trust</value><footnoteId id="F1"/></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Class A Common Stock</value></securityTitle><transactionDate><value>2003-10-24</value></transactionDate><transactionCoding><transactionFormType>5</transactionFormType><transactionCode>Z</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>20000</value></transactionShares><transactionPricePerShare><value>0</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>0</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>By Voting Trust</value><footnoteId id="F1"/></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Class A Common Stock</value></securityTitle><transactionDate><value>2003-10-24</value></transactionDate><transactionCoding><transactionFormType>5</transactionFormType><transactionCode>Z</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>20000</value></transactionShares><transactionPricePerShare><value>0</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>20000</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>By Trust</value><footnoteId id="F1"/></natureOfOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeHolding><securityTitle><value>Class A Common Stock</value></securityTitle><postTransactionAmounts><sharesOwnedFollowingTransaction><value>200</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>See Note</value><footnoteId id="F2"/></natureOfOwnership></ownershipNature></nonDerivativeHolding></nonDerivativeTable><derivativeTable><derivativeTransaction><securityTitle><value>Class B Common Stock</value></securityTitle><conversionOrExercisePrice><footnoteId id="F3"/></conversionOrExercisePrice><transactionDate><value>2003-10-24</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>C</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>20000</value></transactionShares><transactionPricePerShare><value>0</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><footnoteId id="F3"/></exerciseDate><expirationDate><footnoteId id="F3"/></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Class A Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>20000</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>182376</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>By Voting Trust</value><footnoteId id="F1"/></natureOfOwnership></ownershipNature></derivativeTransaction><derivativeHolding><securityTitle><value>Class B Common Stock</value></securityTitle><conversionOrExercisePrice><footnoteId id="F3"/></conversionOrExercisePrice><exerciseDate><footnoteId id="F3"/></exerciseDate><expirationDate><footnoteId id="F3"/></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Class A Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>21082</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>21082</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>By Voting Trust</value><footnoteId id="F4"/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Class B Common Stock</value></securityTitle><conversionOrExercisePrice><footnoteId id="F3"/></conversionOrExercisePrice><exerciseDate><footnoteId id="F3"/></exerciseDate><expirationDate><footnoteId id="F3"/></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Class A Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>21082</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>21082</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>By Voting Trust</value><footnoteId id="F5"/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Class B Common Stock</value></securityTitle><conversionOrExercisePrice><footnoteId id="F3"/></conversionOrExercisePrice><exerciseDate><footnoteId id="F3"/></exerciseDate><expirationDate><footnoteId id="F3"/></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Class A Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>21082</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>21082</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>By Voting Trust</value><footnoteId id="F6"/></natureOfOwnership></ownershipNature></derivativeHolding></derivativeTable><footnotes><footnote id="F1">Voting trust certificates or shares, as the case may be, are held by Jill Schnitzer Edelson and Richard H. Edelson, Trustees U/A/D 2/22/95, F/B/O Jill Schnitzer Edelson.</footnote><footnote id="F2">By Jill Schnitzer Edelson, as custodian under Ohio Uniform Transfers to Minors Act, F/B/O Lauren R. Edelson.</footnote><footnote id="F3">Class B Common Stock is immediately convertible on a one-for-one basis into Class A Common Stock and has no expiration date.</footnote><footnote id="F4">Voting trust certificates are held by Jill Schnitzer Edelson, Family Trustee, and Dina S. Meier, Independent Trustee, U/A/D December 22, 1994 F/B/O Brooke Danielle Edelson.</footnote><footnote id="F5">Voting trust certificates are held by Jill Schnitzer Edelson, Family Trustee, and Dina S. Meier, Independent Trustee, U/A/D December 22, 1994 F/B/O Lauren Rachelle Edelson.</footnote><footnote id="F6">Voting trust certificates are held by Jill Schnitzer Edelson, Family Trustee, and Dina S. Meier, Independent Trustee, U/A/D November 3, 1997 F/B/O Brendan Zane Edelson.</footnote></footnotes><remarks/><ownerSignature><signatureName>Ilene Davidson, Attorney-In-Fact</signatureName><signatureDate>2003-10-27</signatureDate></ownerSignature></ownershipDocument>

