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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-11-28</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001381271</rptOwnerCik>
            <rptOwnerName>Ramstad Peter M</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>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, HR and Bus. Development</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-11-28</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>751</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>28.44</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1607.483</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1.022</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>The Toro Company Investment, Savings &amp; ESOP</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F3">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 Plan:  .003 shares of common stock on January 11, 2008, .003 shares of common stock on April 11, 2008, .005 shares of common stock on July 11, 2008, and .005 shares of common stock on October 17, 2008.  Also includes an account adjustment (rounding) of .0003 shares of common stock.</footnote>
        <footnote id="F1">Represents shares of common stock withheld for the payment of taxes on November 28, 2008 (the next preceding date following the November 27, 2008 vesting date, on which there was a regular trading session reported by the New York Stock Exchange) in connection with the vesting of the employment inducement grant of 2,300 restricted shares of common stock (the &quot;Inducement Grant&quot;) awarded to the reporting person on November 30, 2006.  The award of the Inducement Grant was previously reported on a Form 3 by the reporting person on December 4, 2006, and the terms of the Inducement Grant are described in Exhibit 10(d) to the issuer's Form 10-Q for the quarter ended February 2, 2007 and filed on March 13, 2007.</footnote>
        <footnote id="F2">Includes the following shares of Common Stock acquired by the reporting person under The Toro Company Dividend Reinvestment Plan: 7.134 shares of common stock  on January 11, 2008; 8.422 shares of common stock on April 11, 2008; 11.489 shares of common stock on July 11, 2008; and 10.976 shares of sommon stock on October 17, 2008.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Stacy L. Bogart, Atty-in-Fact</signatureName>
        <signatureDate>2008-12-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0303
4
2008-11-28
0000737758
TORO CO
TTC
0001381271
Ramstad Peter M
8111 LYNDALE AVENUE SOUTH
BLOOMINGTON
MN
55420-1196
0
1
0
0
VP, HR and Bus. Development
Common Stock
2008-11-28
4
F
0
751
28.44
D
1607.483
D
Common Stock
1.022
I
The Toro Company Investment, Savings & ESOP
Includes the following shares of common stock acquired by the reporting person under the dividend reinvestment feature of The Toro Company Investment, Savings & ESOP Plan:  .003 shares of common stock on January 11, 2008, .003 shares of common stock on April 11, 2008, .005 shares of common stock on July 11, 2008, and .005 shares of common stock on October 17, 2008.  Also includes an account adjustment (rounding) of .0003 shares of common stock.
Represents shares of common stock withheld for the payment of taxes on November 28, 2008 (the next preceding date following the November 27, 2008 vesting date, on which there was a regular trading session reported by the New York Stock Exchange) in connection with the vesting of the employment inducement grant of 2,300 restricted shares of common stock (the "Inducement Grant") awarded to the reporting person on November 30, 2006.  The award of the Inducement Grant was previously reported on a Form 3 by the reporting person on December 4, 2006, and the terms of the Inducement Grant are described in Exhibit 10(d) to the issuer's Form 10-Q for the quarter ended February 2, 2007 and filed on March 13, 2007.
Includes the following shares of Common Stock acquired by the reporting person under The Toro Company Dividend Reinvestment Plan: 7.134 shares of common stock  on January 11, 2008; 8.422 shares of common stock on April 11, 2008; 11.489 shares of common stock on July 11, 2008; and 10.976 shares of sommon stock on October 17, 2008.
Stacy L. Bogart, Atty-in-Fact
2008-12-02