<SUBMISSION>
<ACCESSION-NUMBER>0000895419-08-000060
<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>PLASTINA FRANCO
<CIK>0001247740
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>000-21154
<FILM-NUMBER>081056815
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>935 STEWART DRIVE
<CITY>SUNNYVALE
<STATE>CA
<ZIP>94085
<PHONE>4087312706
</BUSINESS-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>0001247740</rptOwnerCik>
            <rptOwnerName>PLASTINA FRANCO</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>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </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>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8750</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>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2008-12-31</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2015-09-02</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>COMMON STOCK</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5000</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;).  Shares awarded will vest on September 2, 2009 provided the recipient continues service until that date as a member of the Board of Directors of Cree, Inc. or as an employee of Cree, Inc. or a related &quot;Employer&quot; as defined in the Plan.</footnote>
        <footnote id="F2">The option vests and becomes exercisable as to one-fourth of the shares on each of December 31, 2008, March 31, 2009, June 30, 2009 and September 30, 2009 or, if earlier, upon the election of directors at the 2009 Annual Meeting of Shareholders, provided the recipient continues service until such dates as a member of the Board of Directors of Cree, Inc. or as an employee of Cree, Inc. or a related &quot;Employer&quot; as defined in the Plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Franco Plastina</signatureName>
        <signatureDate>2008-09-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
