-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 SIlUvRDooiHt6DatjNd6P/yrx0+NhtRuQ41/zYsFN683AB6GG2LMjV7kGbEFA0ms
 WiLrteMtLnV3+RC1USY2GA==

<SEC-DOCUMENT>0001365133-10-000007.txt : 20100602
<SEC-HEADER>0001365133-10-000007.hdr.sgml : 20100602
<ACCEPTANCE-DATETIME>20100602182523
ACCESSION NUMBER:		0001365133-10-000007
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100528
FILED AS OF DATE:		20100602
DATE AS OF CHANGE:		20100602

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HOREJSI STEWART R
		CENTRAL INDEX KEY:			0001246903

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-04605
		FILM NUMBER:		10874017

	MAIL ADDRESS:	
		STREET 1:		200 SOUTH SANTA FE
		CITY:			SALINA
		STATE:			KS
		ZIP:			67401

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FIRST OPPORTUNITY FUND INC
		CENTRAL INDEX KEY:			0000790202
		STANDARD INDUSTRIAL CLASSIFICATION:	UNKNOWN SIC - 0000 [0000]
		IRS NUMBER:				133341573
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		2344 SPRUCE STREET
		STREET 2:		SUITE A
		CITY:			BOULDER
		STATE:			CO
		ZIP:			80302
		BUSINESS PHONE:		3034445483

	MAIL ADDRESS:	
		STREET 1:		2344 SPRUCE STREET
		STREET 2:		SUITE A
		CITY:			BOULDER
		STATE:			CO
		ZIP:			80302

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FIRST FINANCIAL FUND INC
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FIRST SAVINGS & BANKING INSTITUTIONS FUND INC
		DATE OF NAME CHANGE:	19860402

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CICIORA SUSAN L
		CENTRAL INDEX KEY:			0001245558

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-04605
		FILM NUMBER:		10874015

	MAIL ADDRESS:	
		STREET 1:		2344 SPRUCE STREET, STE A
		CITY:			BOULDER
		STATE:			CO
		ZIP:			80302

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MILDRED B. HOREJSI TRUST
		CENTRAL INDEX KEY:			0001365133
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-04605
		FILM NUMBER:		10874016

	BUSINESS ADDRESS:	
		STREET 1:		1029 WEST 3RD AVENUE, SUITE 400
		CITY:			ANCHORAGE
		STATE:			AK
		ZIP:			99503
		BUSINESS PHONE:		(303) 442-2156

	MAIL ADDRESS:	
		STREET 1:		1029 WEST 3RD AVENUE, SUITE 400
		CITY:			ANCHORAGE
		STATE:			AK
		ZIP:			99503

	FORMER NAME:	
		FORMER CONFORMED NAME:	Mildred B. Horejsi Trust
		DATE OF NAME CHANGE:	20060605
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-05-28</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000790202</issuerCik>
        <issuerName>FIRST OPPORTUNITY FUND INC</issuerName>
        <issuerTradingSymbol>FOFI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001365133</rptOwnerCik>
            <rptOwnerName>MILDRED B. HOREJSI TRUST</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1029 WEST 3RD AVENUE, SUITE 400</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ANCHORAGE</rptOwnerCity>
            <rptOwnerState>AK</rptOwnerState>
            <rptOwnerZipCode>99503</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001246903</rptOwnerCik>
            <rptOwnerName>HOREJSI STEWART R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 SOUTH SANTA FE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SALINA</rptOwnerCity>
            <rptOwnerState>KS</rptOwnerState>
            <rptOwnerZipCode>67401</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001245558</rptOwnerCik>
            <rptOwnerName>CICIORA SUSAN L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2344 SPRUCE STREET, STE A</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOULDER</rptOwnerCity>
            <rptOwnerState>CO</rptOwnerState>
            <rptOwnerZipCode>80302</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>2010-05-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>973</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2139374</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-06-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4132</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.21</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2143506</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-06-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.26</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2148506</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-06-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2400</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2150906</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The trustees of the Mildred B. Horejsi Trust (the &quot;Mildred Trust&quot;) are Alaska Trust Company (&quot;Alaska Trust&quot;), Susan L. Ciciora and Brian Sippy. Such trustees may be deemed to control the Mildred Trust and may be deemed to possess indirect beneficial ownership of the Shares held by the Mildred Trust. However, none of the trustees, acting alone, can vote or exercise dispositive authority over Shares held by the Mildred Trust. Accordingly, Alaska Trust, Ms. Ciciora and Mr. Sippy disclaim beneficial ownership of the Shares beneficially owned, directly or indirectly, by the Mildred Trust. In addition to serving as a trustee, Ms. Ciciora is also a beneficiary of the Mildred Trust.

As a result of his advisory role with the Mildred Trust, Stewart R. Horejsi may be deemed to have indirect beneficial ownership of the Shares directly beneficially owned by the Mildred Trust. However, Mr. Horejsi disclaims such beneficial ownership of the Shares directly beneficially held by the Mildred Trust.</footnote>
        <footnote id="F2">Trusts affiliated with the Mildred Trust, including the Lola Brown Trust No. 1B, the Susan L. Ciciora Trust, and the Stewart R. Horejsi Trust No. 2, own an aggregate of 10,330,199 Shares of the Fund following these transactions.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Douglas J. Blattmachr, President, Alaska Trust Company, trustee of the Mildred B. Horejsi Trust</signatureName>
        <signatureDate>2010-06-02</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Stewart R. Horejsi</signatureName>
        <signatureDate>2010-06-02</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Susan L. Ciciora</signatureName>
        <signatureDate>2010-06-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----