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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2015-12-07</periodOfReport>

    <issuer>
        <issuerCik>0000053669</issuerCik>
        <issuerName>JOHNSON CONTROLS INC</issuerName>
        <issuerTradingSymbol>JCI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001292960</rptOwnerCik>
            <rptOwnerName>Molinaroli Alex A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>5757 N. GREEN BAY AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>P.O. BOX 591</rptOwnerStreet2>
            <rptOwnerCity>MILWAUKEE</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>53201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>Chairman &amp; CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2015-12-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>64356</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>42.15</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>374880.79</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>50348.87</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by 401(k) Trustee</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares withheld to satisfy tax withholding obligations upon the vesting of performance share units for the three-year performance period ended September 30, 2015.</footnote>
        <footnote id="F2">Includes 7147 shares acquired via dividend reinvestment on April 2, July 2, and October 2, 2013; January 6, April 2, July 2, and October 2, 2014; and January 5, April 2, July 2 and October 2, 2015 at prices ranging from $34.21 to
$50.91 per share.</footnote>
        <footnote id="F3">The number of underlying securities is based on the stock fund balance on December 7, 2015.  The actual number of shares issuable upon the distribution date is not determinable since the stock fund is a unitized account consisting of 96% company stock and 4% money market fund. The stock account balance reflected in this report is based on a December 7, 2015, stock fund price of $42.15 per share.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Angela M. Blair, Attorney-in-fact for Alex A. Molinaroli</signatureName>
        <signatureDate>2015-12-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
