<?xml version="1.0"?>
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    <periodOfReport>2013-12-03</periodOfReport>

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    <issuer>
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        <issuerName>UNIFI INC</issuerName>
        <issuerTradingSymbol>UFI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
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            <rptOwnerName>JASPER WILLIAM L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
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            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>GREENSBORO</rptOwnerCity>
            <rptOwnerState>NC</rptOwnerState>
            <rptOwnerZipCode>27455</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
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            <isOfficer>1</isOfficer>
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            <isOther>0</isOther>
            <officerTitle>Chairman and CEO</officerTitle>
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                <value></value>
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            <exerciseDate>
                <footnoteId id="F1"/>
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    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Options vested and became exercisable on the date that the closing price of the Registrant's common stock on the New York Stock Exchange was at least $18.00 per share for thirty (30) consecutive trading days.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/William L. Jasper</signatureName>
        <signatureDate>2013-12-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0306
4
2013-12-03
0
0000100726
UNIFI INC
UFI
0001360012
JASPER WILLIAM L
15 OLD SAYBROOK DRIVE
GREENSBORO
NC
27455
1
1
0
0
Chairman and CEO
COMMON STOCK
2013-12-03
4
M
0
33333
10.2
A
83183
D
COMMON STOCK
2013-12-03
4
M
0
21666
8.67
A
104849
D
COMMON STOCK
2013-12-03
4
M
0
133333
8.16
A
238182
D
COMMON STOCK
2013-12-03
4
F
0
90183
26.66
D
147999
D
COMMON STOCK
2013-12-03
4
D
0
98249
25.59
D
49750
D
STOCK OPTION (Right to Buy)
10.2
2013-12-03
4
M
0
11111
0
D
2006-04-19
2016-04-19
COMMON STOCK
11111
0
D
STOCK OPTION (Right to Buy)
10.2
2013-12-03
4
M
0
11111
0
D
2007-04-19
2016-04-19
COMMON STOCK
11111
0
D
STOCK OPTION (Right to Buy)
10.2
2013-12-03
4
M
0
11111
0
D
2008-04-19
2016-04-19
COMMON STOCK
11111
0
D
STOCK OPTION (Right to Buy)
8.67
2013-12-03
4
M
0
7222
0
D
2006-07-26
2016-07-26
COMMON STOCK
7222
0
D
STOCK OPTION (Right to Buy)
8.67
2013-12-03
4
M
0
7222
0
D
2007-07-26
2016-07-26
COMMON STOCK
7222
0
D
STOCK OPTION (Right to Buy)
8.67
2013-12-03
4
M
0
7222
0
D
2008-07-26
2016-07-26
COMMON STOCK
7222
0
D
STOCK OPTION (Right to Buy)
8.16
2013-12-03
4
M
0
133333
0
D
2017-10-24
COMMON STOCK
133333
0
D
The Options vested and became exercisable on the date that the closing price of the Registrant's common stock on the New York Stock Exchange was at least $18.00 per share for thirty (30) consecutive trading days.
/s/William L. Jasper
2013-12-05