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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-11-03</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001122792</rptOwnerCik>
            <rptOwnerName>COOPER JANET KATHERINE</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>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-11-03</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>534</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7305</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock Units</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9497.979</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>33.78</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-11-03</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F3"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3337</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2009-11-03</value>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-11-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3337</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3337</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F2">Includes the following Common Stock Units acquired by the reporting person under the dividend reinvestment feature of The Toro Company Deferred Compensation Plan for Non-Employee Directors:  29.821 Common Stock Units on January 11, 2008; 33.849 Common Stock Units on April 11, 2008; 46.481 Common Stock Units on July 11, 2008; and 43.797 Common Stock Units on October 17, 2008.  Also includes an account adjustment of .0813 Common Stock Units.</footnote>
        <footnote id="F4">The option vests in three equal annual installments commencing in the year following the date of grant.</footnote>
        <footnote id="F1">Annual Common Stock award for service as a director issued under The Toro Company 2000 Directors Stock Plan.</footnote>
        <footnote id="F3">Annual stock option grant for service as a director issued under The Toro Company 2000 Directors Stock Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Stacy L. Bogart, Atty-In-Fact</signatureName>
        <signatureDate>2008-11-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
[{"type": "4", "sequence": "1", "filename": "doc.xml", "description": "PRIMARY DOCUMENT", "secsgml_size_bytes": 6908}]
X0303
4
2008-11-03
0000737758
TORO CO
TTC
0001122792
COOPER JANET KATHERINE
8111 LYNDALE AVENUE SOUTH
BLOOMINGTON
MN
55420-1196
1
0
0
0
Common Stock
2008-11-03
4
A
0
534
0
A
7305
D
Common Stock Units
9497.979
D
Stock Option
33.78
2008-11-03
4
A
0
3337
0
A
2009-11-03
2018-11-03
Common Stock
3337
3337
D
Includes the following Common Stock Units acquired by the reporting person under the dividend reinvestment feature of The Toro Company Deferred Compensation Plan for Non-Employee Directors:  29.821 Common Stock Units on January 11, 2008; 33.849 Common Stock Units on April 11, 2008; 46.481 Common Stock Units on July 11, 2008; and 43.797 Common Stock Units on October 17, 2008.  Also includes an account adjustment of .0813 Common Stock Units.
The option vests in three equal annual installments commencing in the year following the date of grant.
Annual Common Stock award for service as a director issued under The Toro Company 2000 Directors Stock Plan.
Annual stock option grant for service as a director issued under The Toro Company 2000 Directors Stock Plan.
Stacy L. Bogart, Atty-In-Fact
2008-11-04