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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-05-12</periodOfReport>

    <issuer>
        <issuerCik>0000080661</issuerCik>
        <issuerName>PROGRESSIVE CORP/OH/</issuerName>
        <issuerTradingSymbol>PGR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001396061</rptOwnerCik>
            <rptOwnerName>Burgdoerfer Stuart B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>6300 WILSON MILLS</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MAYFIELD VILLAGE</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>44143</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common</value>
            </securityTitle>
            <transactionDate>
                <value>2017-05-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4053</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>67061</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Restricted stock grant, made pursuant to The Progressive Corporation 2017 Directors Equity Incentive Plan, and which will vest on April 12, 2018.  The Progressive Corporation allowed each director to indicate their preference to receive their compensation for the 2017-2018 term in the form of 100% restricted stock or 60% restricted stock and 40% cash.  The reporting person indicated a preference to receive their compensation in the form of 60% restricted stock and 40% cash.  After considering such preference, the Compensation Committee granted a restricted stock award representing 60% of the reporting person's compensation for the 2017-2018 term, and authorized a cash payment on April 12, 2018 for the remaining 40% of the reporting person's compensation.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ David M. Coffey, By Power of Attorney</signatureName>
        <signatureDate>2017-05-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
