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

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2013-12-05</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000909954</issuerCik>
        <issuerName>GREEN MOUNTAIN COFFEE ROASTERS INC</issuerName>
        <issuerTradingSymbol>GMCR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001593545</rptOwnerCik>
            <rptOwnerName>Whoriskey John F.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>33 COFFEE LANE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>WATERBURY</rptOwnerCity>
            <rptOwnerState>VT</rptOwnerState>
            <rptOwnerZipCode>05676</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Pres. - US and Marketing</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>GMCR Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>536802.26</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F2"/>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>GMCR Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>362</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F2"/>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>GMCR Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>318</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>GMCR NQ Stock Options</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>30.79</value>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F6"/>
            </exerciseDate>
            <expirationDate>
                <value>2020-03-11</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>GMCR Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2250</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>GMCR NQ Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>61.71</value>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F7"/>
            </exerciseDate>
            <expirationDate>
                <value>2021-03-10</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>GMCR Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4500</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>GMCR NQ Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>54.12</value>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F8"/>
            </exerciseDate>
            <expirationDate>
                <value>2022-03-22</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>GMCR Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3622</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>GMCR NQ Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>44.26</value>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F9"/>
            </exerciseDate>
            <expirationDate>
                <value>2022-04-23</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>GMCR Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3013</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>GMCR NQ Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>51.56</value>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F10"/>
            </exerciseDate>
            <expirationDate>
                <value>2023-03-07</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>GMCR Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4457</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Includes 981.26 shares of GMCR common stock purchased under the Green Mountain Coffee Roasters, Inc. Amended and Restated Employee Stock Purchase Plan.</footnote>
        <footnote id="F2">Each restricted stock unit represents a contingent right to receive one share of GMCR common stock.</footnote>
        <footnote id="F3">On March 22, 2012 the reporting person was granted 543 restricted stock units, which vest in four equal annual installments.  On March 23, 2013 the first installment of 181 restricted stock units vested.</footnote>
        <footnote id="F4">On April 23, 2012 the reporting person was granted 452 restricted stock units, which vest in four equal annual installments. On April 24, 2013 the first installment of 134 restricted stock units vested.</footnote>
        <footnote id="F5">1 for 1</footnote>
        <footnote id="F6">This option was granted on March 11, 2010 as an option to purchase 9,000 shares of GMCR common stock. The option vests in four equal annual installments, with the first installment vesting on March 11, 2011.  The reporting person previously exercised 6,750 shares underlying this option.</footnote>
        <footnote id="F7">Option vests in four equal installments, with the first installment vesting on March 10, 2012, the first anniversary of the grant date.</footnote>
        <footnote id="F8">Option vests in four equal installments, with the first installment vesting on March 22, 2013, the first anniversary of the grant date.</footnote>
        <footnote id="F9">Option vests in four equal installments, with the first installment vesting on April 23, 2013, the first anniversary of the grant date.</footnote>
        <footnote id="F10">Option vests in four equal installments, with the first installment vesting on March 7, 2014, the first anniversary of the grant date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Sonia G. Cudd, Pursuant to a Power of Attorney</signatureName>
        <signatureDate>2013-12-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
