Exhibit 99.1350CERT


     Certification Pursuant to Section 906 of the Sarbanes Oxley Act


I, Robert C. Doll, Jr., Chief Executive Officer of BlackRock MuniHoldings
Fund, Inc. (the "Fund"), certify that:

1. The N-CSR/A of the Fund (the "Report") fully complies with the requirements
   of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2. The information contained in the Report fairly presents, in all material
   respects, the financial condition and results of operations of the Fund.


Dated: June 7, 2007


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



A signed original of this written statement required by Section 906, or other
document authenticating, acknowledging, or otherwise adopting the signature
that appears in typed form within the electronic version of this written
statement required by Section 906, has been provided to BlackRock MuniHoldings
Fund, Inc. and will be retained by BlackRock MuniHoldings Fund, Inc. and
furnished to the Securities and Exchange Commission or its staff upon request.



Exhibit 99.1350CERT


     Certification Pursuant to Section 906 of the Sarbanes Oxley Act


I, Donald C. Burke, Chief Financial Officer of BlackRock MuniHoldings Fund,
Inc. (the "Fund"), certify that:

1. The N-CSR/A of the Fund (the "Report") fully complies with the requirements
   of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2. The information contained in the Report fairly presents, in all material
   respects, the financial condition and results of operations of the Fund.


Dated: June 7, 2007


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


A signed original of this written statement required by Section 906, or other
document authenticating, acknowledging, or otherwise adopting the signature
that appears in typed form within the electronic version of this written
statement required by Section 906, has been provided to BlackRock MuniHoldings
Fund, Inc. and will be retained by BlackRock MuniHoldings Fund, Inc. and
furnished to the Securities and Exchange Commission or its staff upon request.