<SUBMISSION>
<ACCESSION-NUMBER>0000895419-08-000059
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20080902
<FILING-DATE>20080904
<DATE-OF-FILING-DATE-CHANGE>20080904
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>CREE INC
<CIK>0000895419
<ASSIGNED-SIC>3674
<IRS-NUMBER>561572719
<STATE-OF-INCORPORATION>NC
<FISCAL-YEAR-END>0628
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>4600 SILICON DR
<CITY>DURHAM
<STATE>NC
<ZIP>27703
<PHONE>9193135300
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>4600 SILICON DR
<CITY>DURHAM
<STATE>NC
<ZIP>27703-8475
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>CREE RESEARCH INC /NC/
<DATE-CHANGED>19940224
</FORMER-COMPANY>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>Kelley Stephen Douglas
<CIK>0001443674
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>000-21154
<FILM-NUMBER>081056808
</FILING-VALUES>
<BUSINESS-ADDRESS>
<PHONE>919-313-5797
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>1716 MACGREGOR DRIVE
<CITY>PLANO
<STATE>TX
<ZIP>75093
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-09-02</periodOfReport>

    <issuer>
        <issuerCik>0000895419</issuerCik>
        <issuerName>CREE INC</issuerName>
        <issuerTradingSymbol>CREE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001443674</rptOwnerCik>
            <rptOwnerName>Kelley Stephen Douglas</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CREE, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>4600 SILICON DRIVE</rptOwnerStreet2>
            <rptOwnerCity>DURHAM</rptOwnerCity>
            <rptOwnerState>NC</rptOwnerState>
            <rptOwnerZipCode>27703</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EXECUTIVE VICE PRESIDENT, COO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2008-09-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>20000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>20000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>NONQUALIFIED STOCK OPTION (RIGHT TO BUY)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>22.90</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-09-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>80000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2009-09-02</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2015-09-02</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>COMMON STOCK</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>80000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>80000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Shares of restricted stock awarded under the Cree, Inc. 2004 Long-Term Incentive Compensation Plan, as amended (the &quot;Plan&quot;).  One-fifth of the shares awarded will vest on each of September 1, 2009, September 1, 2010, September 1, 2011, September 1, 2012 and September 1, 2013, provided the recipient continues service until such dates as an employee or director of Cree, Inc. or as an employee of a related &quot;Employer&quot; as defined in the Plan.</footnote>
        <footnote id="F2">Option vests and becomes exercisable as to one-third of the shares on each of September 2, 2009, September 2, 2010 and September 2, 2011, provided the recipient continues service until such dates as an employee or director of Cree, Inc. or as an employee of a related &quot;Employer&quot; as defined in the Plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Stephen D. Kelley</signatureName>
        <signatureDate>2008-09-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
