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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-09-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000906326</issuerCik>
        <issuerName>RURAL/METRO CORP /DE/</issuerName>
        <issuerTradingSymbol>RURL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001430708</rptOwnerCik>
            <rptOwnerName>Shackelton Christopher S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>825 THIRD AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>36TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Rural/Metro Corp</value>
            </securityTitle>
            <transactionDate>
                <value>2008-09-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5200</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.8015</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1692659</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Note 1</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These securities are held directly by an investment limited partnership of which Coliseum Capital, LLC, a Deleware limited liability company, is general partner, and Coliseum Capital Management, LLC, a Deleware limited liability company, (together with Coliseum Capital, LLC, &quot;Coliseum&quot;), is investment advisor. Mr. Shackelton is an employee of Coliseum and a director of the Issuer. Each of Mr. Shackelton and Coliseum disclaims beneficial ownership of these securities except to the extent of that person's pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Chris Shackelton, Manager</signatureName>
        <signatureDate>2008-09-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
