Exhibit 99.1350CERT


     Certification Pursuant to Rule 30a-2(b) under the 1940 Act and
                  Section 906 of the Sarbanes Oxley Act


Pursuant to 18 U.S.C.  1350, the undersigned officer of BlackRock MuniHoldings
Fund, Inc. (the "Registrant"), hereby certifies, to the best of his knowledge,
that the Registrant's Report on Form N-CSR for the period ended April 30, 2007,
(the "Report") fully complies with the requirements of Section 13(a) of the
Securities Exchange Act of 1934, as amended, and that the information contained
in the Report fairly presents, in all material respects, the financial
condition and results of operations of the Registrant.


Date: June 19, 2007


/s/ Robert C. Doll, Jr.
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Robert C. Doll, Jr., Chief Executive Officer of
BlackRock MuniHoldings Fund, Inc.


Pursuant to 18 U.S.C.  1350, the undersigned officer of BlackRock MuniHoldings
Fund, Inc. (the "Registrant"), hereby certifies, to the best of his knowledge,
that the Registrant's Report on Form N-CSR for the period ended April 30, 2007,
(the "Report") fully complies with the requirements of Section 13(a) of the
Securities Exchange Act of 1934, as amended, and that the information contained
in the Report fairly presents, in all material respects, the financial
condition and results of operations of the Registrant.


Date: June 19, 2007


/s/ Donald C. Burke
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Donald C. Burke, Chief Financial Officer of
BlackRock MuniHoldings Fund, Inc.



This certification is being furnished pursuant to Rule 30a-2(b) under the
Investment Company Act of 1940, as amended, and 18 U.S.C. Section 1350 and is
not being filed as part of the Form N-CSR with the Securities and Exchange
Commission