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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2019-05-07</periodOfReport>

    <dateOfOriginalSubmission>2019-05-09</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000047111</issuerCik>
        <issuerName>HERSHEY CO</issuerName>
        <issuerTradingSymbol>HSY</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000938543</rptOwnerCik>
            <rptOwnerName>HERSHEY TRUST CO TRUSTEE IN TRUST FOR MILTON HERSHEY SCHOOL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>100 MANSION ROAD EAST</rptOwnerStreet1>
            <rptOwnerStreet2>P O BOX 445</rptOwnerStreet2>
            <rptOwnerCity>HERSHEY</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>17033</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $1.00 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2019-05-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>293958</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>123.6837</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2735650</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $1.00 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2019-05-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>262959</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>124.8187</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2472691</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, $1.00 par value</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>102330</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Hershey Trust Company</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Class B Common Stock, $1.00 par value</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>124.86</value>
                <footnoteId id="F6"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F5"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, $1.00 par value</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>60612012</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>60612012</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 Plan adopted by the reporting person on November 29, 2018.  Accordingly, the reporting person had no discretion with regard to the timing of the transactions.</footnote>
        <footnote id="F2">The price reported in Column 4 is a weighted average price.  The shares were sold in multiple transactions at prices ranging from $122.54 to $124.19, inclusive.  The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, to any security holder of The Hershey Company, or to The Hershey Company, upon request, full information regarding the number of shares sold at each separate price within the range set forth above.</footnote>
        <footnote id="F3">The price reported in Column 4 is a weighted average price.  The shares were sold in multiple transactions at prices ranging from $123.69 to $125.46, inclusive.  The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, to any security holder of The Hershey Company, or to The Hershey Company, upon request, full information regarding the number of shares sold at each separate price within the range set forth above.</footnote>
        <footnote id="F4">Hershey Trust Company is wholly owned by the Milton Hershey School Trust and is trustee for the Milton Hershey School Trust.</footnote>
        <footnote id="F5">All shares of Class B common stock, $1.00 par value, are convertible share-for-share into common stock, $1.00 par value, at any time, and without payment other than for the fact of conversion.  There is no expiration date.</footnote>
        <footnote id="F6">Conversion price is the current market price ($124.86 represents the closing price on 5/8/2019).</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Matthew Jacolik</signatureName>
        <signatureDate>2019-05-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
