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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2011-02-27</periodOfReport>

    <issuer>
        <issuerCik>0000700863</issuerCik>
        <issuerName>SUSQUEHANNA BANCSHARES INC</issuerName>
        <issuerTradingSymbol>SUSQ</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001370078</rptOwnerCik>
            <rptOwnerName>Lizza Joseph R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>26 N. CEDAR STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LITITZ</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>17543</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>SVP &amp; Group Executive</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2011-02-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>117</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>9.69</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>18340.7232</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The 117 shares of common stock disposed of represent a portion of a 1,000 share restricted stock grant issued on February 27, 2008 that was previously reported on a Form 4 filed with the Securities and Exchange Commission on February 29, 2008. One-third of the shares under this grant vested on each of February 27, 2009, 2010, and 2011. The shares disposed of were withheld to satisfy the reporting person's tax withholding obligation incident to the 334 shares that vested on February 27, 2011.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Abram G. Koser, attorney-in-fact for Joseph R. Lizza</signatureName>
        <signatureDate>2011-03-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
