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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2009-01-12</periodOfReport>

    <dateOfOriginalSubmission>2009-01-14</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000888693</issuerCik>
        <issuerName>ISCO INTERNATIONAL INC</issuerName>
        <issuerTradingSymbol>ISO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001267498</rptOwnerCik>
            <rptOwnerName>ABDELMONEM AMR</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ISCO INTERNATIONAL INC</rptOwnerStreet1>
            <rptOwnerStreet2>1001 CAMBRIDGE DRIVE</rptOwnerStreet2>
            <rptOwnerCity>ELK GROVE</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60007</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Opr Off &amp; Chief Tech Off</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.001</value>
            </securityTitle>
            <transactionDate>
                <value>2009-01-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>600000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2502000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Restricted shares of common stock granted to Mr. Abdelmonem under the issuer's 2003 Equity Incentive Plan.</footnote>
        <footnote id="F2">No purchase price was paid for this grant of restricted stock.</footnote>
    </footnotes>

    <remarks>This Form 4/A is being filed to correct the original Form 4 filed on January 14, 2008 for Mr. Abdelmonem which incorrectly reported that Mr. Abdelmonem sold 236,700 shares of common stock to ISCO International, Inc. on January 12, 2009 to satisfy tax withholding obligations.</remarks>

    <ownerSignature>
        <signatureName>/s/ Rachel Williams Mantz, Attorney-in-fact for Amr Abdelmonem</signatureName>
        <signatureDate>2009-01-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
