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

    <schemaVersion>X0304</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2011-08-01</periodOfReport>

    <issuer>
        <issuerCik>0000027904</issuerCik>
        <issuerName>DELTA AIR LINES INC /DE/</issuerName>
        <issuerTradingSymbol>DAL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001504635</rptOwnerCik>
            <rptOwnerName>FRANKLIN SHIRLEY C.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O DELTA AIR LINES, INC., DEPT. 981</rptOwnerStreet1>
            <rptOwnerStreet2>P.O. BOX 20574</rptOwnerStreet2>
            <rptOwnerCity>ATLANTA,</rptOwnerCity>
            <rptOwnerState>GA</rptOwnerState>
            <rptOwnerZipCode>30320</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>2011-08-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>14750</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>14750</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Non-employee members of Delta's Board of Directors receive an annual restricted stock award.  The shares reported in this Form 4 represent the annual restricted stock award to the Reporting Person, as approved by the Board of Directors on July 20, 2011.  In accordance with Delta's Equity Award Grant Policy, the grant date of the award is August 1, 2011, the third business day following the date on which Delta publicly announced its financial results for the June 2011 quarter. The shares were acquired in a transaction exempt under Rule 16b-3(d).</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Jan M. Davidson as attorney-in-fact for Shirley C. Franklin</signatureName>
        <signatureDate>2011-08-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
