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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-12-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000884382</issuerCik>
        <issuerName>PRIMEDIA INC</issuerName>
        <issuerTradingSymbol>PRM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001206581</rptOwnerCik>
            <rptOwnerName>GOLKIN PERRY</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1></rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity></rptOwnerCity>
            <rptOwnerState></rptOwnerState>
            <rptOwnerZipCode></rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-12-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3273.8095</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>4.2</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>84157.6556</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">As Director of PRIMEDIA Inc. (&quot;PRIMEDIA&quot;), the reporting person has elected to have his director's fee paid in Common Stock, par value $0.01 per share of PRIMEDIA (the
&quot;Common Stock&quot;).  The Common Stock acquired by the reporting person represents shares of Common Stock credited in lieu of payment of director's fees for the quarter ended December 31, 2010.</footnote>
        <footnote id="F2">Quarterly director's fees are $13,750.  The per share price used in the calculation of total shares of Common Stock credited was $4.20 per share, the closing price of the Common Stock on the New York Stock Exchange on December 31, 2010.</footnote>
    </footnotes>

    <remarks>The reporting person is an Advisory Partner of Kohlberg Kravis Roberts &amp; Co. L.P. (together with its affiliates, as applicable, &quot;KKR&quot;) and a General Partner of KKR Associates, L.P.  KKR 1996 Fund L.P. and other KKR sponsored entities have filed separate Section 16 reports reporting shares of PRIMEDIA that they may be deemed to beneficially own.  The reporting person disclaims beneficial ownership of any shares of PRIMEDIA that may be deemed to be owned by such KKR sponsored entities.</remarks>

    <ownerSignature>
        <signatureName>/s/ RICHARD KREIDER, as Attorney-in-Fact (See Power of Attorney)</signatureName>
        <signatureDate>2011-01-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
