    <SEC-DOCUMENT>0001193125-18-074635-index.html : 20180308
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    <ACCEPTANCE-DATETIME>20180308112208
    ACCESSION NUMBER:		0001193125-18-074635
    CONFORMED SUBMISSION TYPE:	N-CSR
    PUBLIC DOCUMENT COUNT:		25
    CONFORMED PERIOD OF REPORT:	20171231
    FILED AS OF DATE:		20180308
    DATE AS OF CHANGE:		20180308
    EFFECTIVENESS DATE:		20180308

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			BlackRock Health Sciences Trust
    		CENTRAL INDEX KEY:			0001314966
    		IRS NUMBER:				000000000
    		STATE OF INCORPORATION:			DE

    	FILING VALUES:
    		FORM TYPE:		N-CSR
    		SEC ACT:		1940 Act
    		SEC FILE NUMBER:	811-21702
    		FILM NUMBER:		18675555

    	BUSINESS ADDRESS:
    		STREET 1:		100 BELLEVUE PARKWAY
    		CITY:			WILMINGTON
    		STATE:			DE
    		ZIP:			19809
    		BUSINESS PHONE:		(888) 825-2257

    	MAIL ADDRESS:
    		STREET 1:		100 BELLEVUE PARKWAY
    		CITY:			WILMINGTON
    		STATE:			DE
    		ZIP:			19809
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    <SEQUENCE>1
    <FILENAME>d516554dncsr.htm
    <DESCRIPTION>BLACKROCK HEALTH SCIENCES TRUST
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    Document 1 - file: d516554dncsr.htm

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    <DESCRIPTION>CERTIFICATION PURSUANT TO SECTION 302
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    <TYPE>EX-99.PROXY.POL
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