September 28, 2022
VIA ELECTRONIC FILING
Securities and Exchange Commission
100 F Street, NE
Judiciary Plaza
Washington, DC 20549
Attention: Division of Investment Management
RE: BlackRock Municipal Bond Fund, Inc.
Post-Effective Amendment No. 73 to the Registration Statement on Form N-1A
(Securities Act File No. 002-57354, Investment Company Act File No. 811-02688)
Ladies and Gentlemen:
Pursuant to Rule 497(j) under the Securities Act of 1933, as amended (the 1933 Act), BlackRock Municipal Bond Fund, Inc. (the Fund) hereby certifies that:
(1) the form of Prospectus and Statement of Additional Information that would have been filed pursuant to Rule 497(c) under the 1933 Act would not have differed from that contained in Post-Effective Amendment No. 73 to the Funds Registration Statement on Form N-1A; and
(2) the text of Post-Effective Amendment No. 73 to the Funds Registration Statement on Form N-1A was filed electronically with the Securities and Exchange Commission on September 23, 2022.
Sincerely,
BlackRock Municipal Bond Fund, Inc.
/s/ Janey Ahn
Janey Ahn
Secretary of the Fund