<SEC-DOCUMENT>0001752724-20-063741-index.html : 20200327
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<ACCEPTANCE-DATETIME>20200327145856
ACCESSION NUMBER:		0001752724-20-063741
CONFORMED SUBMISSION TYPE:	NPORT-P
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200131
FILED AS OF DATE:		20200327
PERIOD START:           	20200731

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BLACKROCK MUNICIPAL INCOME INVESTMENT TRUST
		CENTRAL INDEX KEY:			0001137392
		IRS NUMBER:				510409116
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1031

	FILING VALUES:
		FORM TYPE:		NPORT-P
		SEC ACT:		1940 Act
		SEC FILE NUMBER:	811-10333
		FILM NUMBER:		20751047

	BUSINESS ADDRESS:	
		STREET 1:		100 BELLEVUE PARKWAY
		STREET 2:		MUTUAL FUND DEPARTMENT
		CITY:			WILMINGTON
		STATE:			DE
		ZIP:			19809
		BUSINESS PHONE:		888-825-2257

	MAIL ADDRESS:	
		STREET 1:		100 BELLEVUE PARKWAY
		STREET 2:		MUTUAL FUND DEPARTMENT
		CITY:			WILMINGTON
		STATE:			DE
		ZIP:			19809

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BLACKROCK FLORIDA MUNICIPAL INCOME TRUST
		DATE OF NAME CHANGE:	20010330
</SEC-HEADER>
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Document 1 - file: primary_doc.html

Document 1 - RAW XML: primary_doc.xml

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