Chapman and Cutler LLP
111 West Monroe Street
Chicago, Illinois 60603

July 2, 2019

Securities and Exchange Commission
100 Fifth Street, N.E.
Washington, D.C. 20549

Ladies and Gentlemen:

On behalf of RiverNorth Managed Duration Municipal Income Fund, Inc. (the “Fund” ), we enclose herewith for filing pursuant to Section 12(b) of the Securities Exchange Act of 1934, as amended, the Fund’s Registration Statement on Form 8-A covering shares of the Fund’s common stock, $0.0001 par value per share (the “Shares” ).

On March 20, 2019, the Fund filed with the Securities and Exchange Commission its initial Registration Statement on Form N-2 (Registration Nos. 333-230421 and 811-23434) to register the Shares under the Securities Act of 1933, as amended.

The Shares are being listed on the New York Stock Exchange LLC and, accordingly, a copy of the Form 8-A has been provided to the New York Stock Exchange LLC.

If you have any questions concerning this filing or require any additional information, please contact me at (312) 845-3273.

Enclosures

Securities and Exchange Commission
Washington, D.C.

Form 8-A

For Registration of Certain Classes of Securities
Pursuant to Section 12( b ) or ( g ) of the
Securities Exchange Act of 1934

If this form relates to the registration of a class of securities pursuant to Section 12(b) of the Exchange Act and is effective pursuant to General Instruction A. (c), check the following box.-- [X]

If this form relates to the registration of a class of securities pursuant to Section 12(g) of the Exchange Act and is effective pursuant to General Instruction A. (d), check the following box.-- [  ]

Securities Act registration statement file number to which this form relates: 333-230421

Securities to be registered pursuant to Section 12(b) of the Act:

Securities to be registered pursuant to Section 12(g) of the Act:

Information Required in Registration Statement

The securities to be registered hereunder are shares of common stock, $0.0001 par value per share (the “Shares” ), of RiverNorth Managed Duration Municipal Income Fund, Inc. (the “Registrant” ). An application for listing of the Shares has been filed with the New York Stock Exchange LLC. A description of the Shares is contained under the caption “Description of the Common Shares” in the Preliminary Prospectus, which is a part of Pre-effective Amendment No. 2 to the Registration Statement on Form N-2 (Registration Nos. 333-230421 and 811-23434), filed with the Securities and Exchange Commission on June 24, 2019. Such description is incorporated by reference herein. In addition, the above-referenced description included in any Prospectus relating to the Registration Statement filed with the Commission pursuant to Rule 497 under the Securities Act of 1933, as amended, shall be deemed to be incorporated herein by reference.

Pursuant to the “Instruction as to Exhibits” of Form 8-A, no exhibits are filed herewith or incorporated by reference.

Signature

Pursuant to the requirements of Section 12(b) of the Securities Exchange Act of 1934, the Registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereto duly authorized.

July 2, 2019