<SEC-DOCUMENT>0000844779-18-000106-index.html : 20180327
<SEC-HEADER>0000844779-18-000106.hdr.sgml : 20180327
<ACCEPTANCE-DATETIME>20180327145533
ACCESSION NUMBER:		0000844779-18-000106
CONFORMED SUBMISSION TYPE:	NSAR-A
PUBLIC DOCUMENT COUNT:		4
CONFORMED PERIOD OF REPORT:	20180131
FILED AS OF DATE:		20180327
DATE AS OF CHANGE:		20180327
EFFECTIVENESS DATE:		20180327

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BLACKROCK MUNIYIELD INVESTMENT QUALITY FUND
		CENTRAL INDEX KEY:			0000891188
		IRS NUMBER:				223196058
		FISCAL YEAR END:			0630

	FILING VALUES:
		FORM TYPE:		NSAR-A
		SEC ACT:		1940 Act
		SEC FILE NUMBER:	811-07156
		FILM NUMBER:		18715131

	BUSINESS ADDRESS:	
		STREET 1:		100 BELLEVUE PARKWAY
		CITY:			WILMINGTON
		STATE:			DE
		ZIP:			19809
		BUSINESS PHONE:		800-441-7762

	MAIL ADDRESS:	
		STREET 1:		100 BELLEVUE PARKWAY
		CITY:			WILMINGTON
		STATE:			DE
		ZIP:			19809

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BLACKROCK MUNIYIELD INSURED INVESTMENT FUND
		DATE OF NAME CHANGE:	20080926

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BLACKROCK MUNIYIELD FLORIDA INSURED FUND
		DATE OF NAME CHANGE:	20070611

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MUNIYIELD FLORIDA INSURED FUND /NJ/
		DATE OF NAME CHANGE:	19921217
</SEC-HEADER>
<DOCUMENT>
<TYPE>NSAR-A
<SEQUENCE>1
<FILENAME>LCQSanswer.fil
<TEXT>
Document 1 - file: LCQSanswer.fil

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.77O RULE 10F-3
<SEQUENCE>2
<FILENAME>77o1.txt
<TEXT>
Document 2 - file: 77o1.txt

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.77O RULE 10F-3
<SEQUENCE>3
<FILENAME>77o4.txt
<TEXT>
Document 3 - file: 77o4.txt

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.77O RULE 10F-3
<SEQUENCE>4
<FILENAME>77o5.txt
<TEXT>
Document 4 - file: 77o5.txt

</DOCUMENT>
</SEC-DOCUMENT>