<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-01-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000897723</issuerCik>
        <issuerName>SANMINA-SCI CORP</issuerName>
        <issuerTradingSymbol>SANM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001142616</rptOwnerCik>
            <rptOwnerName>COUDER ALAIN A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1></rptOwnerStreet1>
            <rptOwnerStreet2>2700 NORTH FIRST STREET</rptOwnerStreet2>
            <rptOwnerCity>SAN JOSE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95134</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-01-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>47143</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.35</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>47143</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>259178.837</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">PHANTOM STOCK PURCHASED ON BEHALF OF THE REPORTING PERSON PURSUANT TO THE ISSUER'S DIRECTOR DEFERRED COMPENSATION PLAN (&quot;PLAN&quot;). UNDER SUCH PLAN, PARTICIPANTS MAY ELECT TO DEFER PAYMENT OF THE BOARD RETAINER AND MEETING FEES, WHICH ARE CONVERTED INTO A NUMBER OF SHARE UNITS CALCULATED BY DIVIDING THE AMOUNT OF THE RETAINER AND FEES DEFERRED BY THE CLOSING STOCK PRICE ON THE DAY SUCH AMOUNTS WOULD HAVE OTHERWISE BEEN PAYABLE.  PHANTOM STOCK IS PAID IN THE FORM OF SHARES OF THE ISSUER'S COMMON STOCK (AND CASH IN LIEU OF ANY FRACTIONAL SHARES) FOLLOWING TERMINATION OF THE REPORTING PERSON'S SERVICES AS DIRECTOR.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Chris K. Sadeghian, Attorney-in-Fact</signatureName>
        <signatureDate>2009-01-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
