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

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2006-04-25</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000009801</issuerCik>
        <issuerName>BANTA CORP</issuerName>
        <issuerTradingSymbol>BN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001333099</rptOwnerCik>
            <rptOwnerName>Haugarth Janel S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>225 MAIN STREET</rptOwnerStreet1>
            <rptOwnerStreet2>P. O. BOX 8003</rptOwnerStreet2>
            <rptOwnerCity>MENASHA</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>54952-8003</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>Ronald D. Kneezel, attorney-in-fact</signatureName>
        <signatureDate>2006-04-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
