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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-12-03</periodOfReport>

    <issuer>
        <issuerCik>0000737758</issuerCik>
        <issuerName>TORO CO</issuerName>
        <issuerTradingSymbol>TTC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001382452</rptOwnerCik>
            <rptOwnerName>Happe Michael J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>8111 LYNDALE AVENUE SOUTH</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BLOOMINGTON</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55420-1196</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>General Manager, Commercial</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2902.297</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>The Toro Company Investment, Savings &amp; ESOP</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>28.62</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-12-03</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>7300</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-12-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>7300</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7300</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Includes the following shares of common stock acquired by the reporting person under the dividend reinvestment feature of The Toro Company Investment, Savings &amp; ESOP (IS&amp;ESOP): 8.334 shares acquired on January 11, 2008, 10.292 sharers acquired on April 11, 2008, 13.791 shares acquired on July 11, 2008 and 13.459 shares acquired on October 17, 2008.  Also includes 171.295 shares of common stock acquired by the reporting person through individual contributions and issuer matching contributions to the IS&amp;ESOP and an account adjustment (rounding) of .377 shares of common stock.</footnote>
        <footnote id="F2">The option vests in three equal annual installments commencing on the first anniversary of the date of grant.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Stacy L. Bogart, Atty-in-fact</signatureName>
        <signatureDate>2008-12-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0303
4
2008-12-03
0000737758
TORO CO
TTC
0001382452
Happe Michael J
8111 LYNDALE AVENUE SOUTH
BLOOMINGTON
MN
55420-1196
0
0
0
1
General Manager, Commercial
Common Stock
2902.297
I
The Toro Company Investment, Savings & ESOP
Stock Option
28.62
2008-12-03
4
A
0
7300
0
A
2018-12-03
Common Stock
7300
7300
D
Includes the following shares of common stock acquired by the reporting person under the dividend reinvestment feature of The Toro Company Investment, Savings & ESOP (IS&ESOP): 8.334 shares acquired on January 11, 2008, 10.292 sharers acquired on April 11, 2008, 13.791 shares acquired on July 11, 2008 and 13.459 shares acquired on October 17, 2008.  Also includes 171.295 shares of common stock acquired by the reporting person through individual contributions and issuer matching contributions to the IS&ESOP and an account adjustment (rounding) of .377 shares of common stock.
The option vests in three equal annual installments commencing on the first anniversary of the date of grant.
Stacy L. Bogart, Atty-in-fact
2008-12-05