    <SEC-DOCUMENT>0001193125-24-022389-index.html : 20240202
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    <ACCEPTANCE-DATETIME>20240202084525
    ACCESSION NUMBER:		0001193125-24-022389
    CONFORMED SUBMISSION TYPE:	DEFA14A
    PUBLIC DOCUMENT COUNT:		3
    FILED AS OF DATE:		20240202
    DATE AS OF CHANGE:		20240202

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			GLADSTONE CAPITAL CORP
    		CENTRAL INDEX KEY:			0001143513
    		ORGANIZATION NAME:
    		IRS NUMBER:				542040781
    		STATE OF INCORPORATION:			MD
    		FISCAL YEAR END:			0930

    	FILING VALUES:
    		FORM TYPE:		DEFA14A
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	814-00237
    		FILM NUMBER:		24588906

    	BUSINESS ADDRESS:
    		STREET 1:		1521 WESTBRANCH DRIVE
    		STREET 2:		SUITE 100
    		CITY:			MCLEAN
    		STATE:			VA
    		ZIP:			22102
    		BUSINESS PHONE:		703-287-5800

    	MAIL ADDRESS:
    		STREET 1:		1521 WESTBRANCH DRIVE
    		STREET 2:		SUITE 100
    		CITY:			MCLEAN
    		STATE:			VA
    		ZIP:			22102
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>DEFA14A
    <SEQUENCE>1
    <FILENAME>d675125ddefa14a.htm
    <DESCRIPTION>DEFA14A
    <TEXT>
    Document 1 - file: d675125ddefa14a.htm

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    <TYPE>GRAPHIC
    <SEQUENCE>2
    <FILENAME>g675125txp1g1.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 2 - file: g675125txp1g1.jpg

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    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>3
    <FILENAME>g675125txp2g1.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 3 - file: g675125txp2g1.jpg

    </DOCUMENT>
    </SEC-DOCUMENT>