<?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>0001183473</rptOwnerCik>
            <rptOwnerName>PIERNE JAMES G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>SUSQUEHANNA BANCSHARES, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>26 N. CEDAR STREET</rptOwnerStreet2>
            <rptOwnerCity>LITITZ</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>17543</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>EVP and 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>390</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>9.69</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>39919.2653</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares of restricted stock granted pursuant to a Restricted Stock Agreement (the &quot;Agreement&quot;), dated as of August 19, 2010 and as amended on February 14, 2011. As amended, the Agreement provides that the shares vest upon the first to occur of the following, provided that the reporting person continues to be employed by the Issuer through the applicable date: (i) the second anniversary of the date of the grant; (ii) the reporting person's death; (iii) the reporting person's disability; (iv) the effective date of a change in control event; and (v) the date determined in accordance with the terms and conditions of any employment agreement between the reporting person and the Issuer.</footnote>
        <footnote id="F2">The 390 shares of common stock disposed of represent a portion of a 3,000 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 1,000 shares that vested on February 27, 2011.</footnote>
    </footnotes>

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