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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2006-05-04</periodOfReport>

    <dateOfOriginalSubmission>2006-05-08</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000911673</issuerCik>
        <issuerName>OPINION RESEARCH CORP</issuerName>
        <issuerTradingSymbol>ORCI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001287649</rptOwnerCik>
            <rptOwnerName>CANNELL J CARLO</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>150 CALIFORNIA STREET 5TH FL</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94111</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>2006-05-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4166</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.0834</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>349930</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Through one or more funds</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <remarks>This is a filing by J. Carlo Cannell (&quot;Cannell&quot;).  Mr. Cannell has sole voting and investment control over all securities owned by The Cuttyhunk Fund Limited (&quot;Cuttyhunk&quot;), the Anegada Master Fund, Ltd. (&quot;Anegada&quot;), TE Cannell Portfolio, Ltd. (&quot;TEC&quot;) and Tonga Partners, L.P. (&quot;Tonga&quot; and, collectively, with Cuttyhunk, Anegada and TEC, the &quot;Funds&quot;).  Cuttyhunk owns 128,622 shares, Anegada owns 134,374 shares, TEC owns 94,582 shares, and Tonga owns 215,556 shares.  Mr. Cannell's interest in the shares held by the Funds is limited to the extent of his pecuniary interest therein.</remarks>

    <ownerSignature>
        <signatureName>J. Carlo Cannell</signatureName>
        <signatureDate>2006-05-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
