SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 8-A

                FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                   PURSUANT TO SECTION 12(b) OR 12 (g) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                         PIMCO Municipal Income Fund III
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             (Exact Name of Registrant as Specified in Its Charter)



            Massachusetts                                55-6145593
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(State of Incorporation or Organization)    (I.R.S. Employer Identification No.)

c/o PIMCO Funds Advisors LLC
1345 Avenue of the Americas
New York, New York                                         10105
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(Address of Principal Executive Offices)                 (Zip Code)


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), please 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), please check the following box: |_|


Securities Act registration statement file number pursuant to
which this form relates:    333-98503
                        ------------------
                         (if applicable)

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

Title of Each Class to be so Registered:    Name of Each Exchange on Which Each
                                            Class is to be Registered:
Common Shares of Beneficial Interest
With Par Value $0.00001                     New York Stock Exchange
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Securities to be registered pursuant to Section 12(g) of the Act:   None



INFORMATION REQUIRED IN REGISTRATION STATEMENT

Item 1.  DESCRIPTION OF REGISTRANT'S SECURITIES TO BE REGISTERED.

     Reference is hereby made to the section entitled "Description of Shares" in
the Registration Statement on Form N-2 of PIMCO Municipal Income Fund III, as
filed with the Securities and Exchange Commission (the "Commission") on August
22, 2002 (Securities Act File No. 333-98503 and Investment Company Act File No.
811-21187) (the "Original Registration Statement").

Item 2.   EXHIBITS.

     Pursuant to the Instructions as to Exhibits, no Exhibits are filed herewith
or incorporated herein by reference.

                                    SIGNATURE

     A copy of the Agreement and Declaration of Trust of PIMCO Municipal Income
Fund III is on file with the Secretary of State of The Commonwealth of
Massachusetts, and notice is hereby given that this instrument is executed on
behalf of the Trust by an officer or Trustee of the Trust in his or her capacity
as an officer or Trustee of the Trust and not individually and that the
obligations of or arising out of this instrument are not binding upon any of the
Trustees, officers, or shareholders individually but binding only upon the
assets and property of the Trust.

     Pursuant to the requirements of Section 12 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.

                              PIMCO MUNICIPAL INCOME FUND III



                              By:  /s/ Brian S. Shlissel
                                 ---------------------------------------
                                 Name:    Brian S. Shlissel
                                 Title:   President and Chief Executive
                                          Officer

Date:  September 25, 2002