UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM N-PX

                     ANNUAL REPORT OF PROXY VOTING RECORD OF
                   REGISTERED MANAGEMENT INVESTMENT COMPANIES

                   Investment Company Act file number 811-2794

                              MFS SERIES TRUST III
               (Exact name of registrant as specified in charter)

                500 Boylston Street, Boston, Massachusetts 02116
               (Address of principal executive offices) (Zip code)

                                 Susan S. Newton
                    Massachusetts Financial Services Company
                               500 Boylston Street
                           Boston, Massachusetts 02116
                    (Name and address of agents for service)

       Registrant's telephone number, including area code: (617) 954-5000

                       Date of fiscal year end: January 31

              Date of reporting period: July 1, 2006- June 30, 2007



ITEM 1. PROXY VOTING RECORD.


******************************* FORM N-Px REPORT *******************************

ICA File Number: 811-02794
Reporting Period: 07/01/2006 - 06/30/2007
MFS Series Trust III









============================= MFS HIGH INCOME FUND =============================


CHESAPEAKE ENERGY CORP.

Ticker:       CHK            Security ID:  165167107
Meeting Date: JUN 8, 2007    Meeting Type: Annual
Record Date:  APR 16, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director Frank Keating              For       For        Management
1.2   Elect Director Merrill A. Miller, Jr.     For       For        Management
1.3   Elect Director Frederick B. Whittemore    For       For        Management
2     Amend Omnibus Stock Plan                  For       For        Management
3     Amend Non-Employee Director Stock Option  For       For        Management
      Plan


- --------------------------------------------------------------------------------

FOUNDATION COAL HLDGS INC

Ticker:       FCL            Security ID:  35039W100
Meeting Date: MAY 17, 2007   Meeting Type: Annual
Record Date:  MAR 28, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director James F. Roberts           For       For        Management
1.2   Elect Director David I. Foley             For       For        Management
1.3   Elect Director Alex T. Krueger            For       For        Management
1.4   Elect Director P. Michael Giftos          For       For        Management
1.5   Elect Director Robert C. Scharp           For       For        Management
1.6   Elect Director William J. Crowley, Jr.    For       For        Management
1.7   Elect Director Joel Richards, III         For       For        Management
1.8   Elect Director Thomas V. Shockley, III    For       For        Management
2     Ratify Auditors                           For       For        Management
3     Other Business                            For       Against    Management


- --------------------------------------------------------------------------------

FRONTIERVISION OPERATING PARTNERS L.P.

Ticker:                      Security ID:  35921LAA3
Meeting Date: SEP 12, 2006   Meeting Type: Written Consent
Record Date:  NOV 28, 2005

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1     DEBTORS  FOURTH AMENDED JOINT PLAN OF     None      Did Not    Management
      REORGANIZATION UNDER CHAPTER 11 OF THE              Vote
      BANKRUPTCY CODE DATED NOVEMBER 21, 2005.


- --------------------------------------------------------------------------------

HUNTSMAN CORP

Ticker:       HUN            Security ID:  447011107
Meeting Date: MAY 3, 2007    Meeting Type: Annual
Record Date:  MAR 16, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director Nolan D. Archibald         For       For        Management
1.2   Elect Director H.W. Lichtenberger         For       Withhold   Management
1.3   Elect Director Richard A. Michaelson      For       For        Management
2     Ratify Auditors                           For       For        Management


- --------------------------------------------------------------------------------

ION  MEDIA NETWORKS, INC.

Ticker:       ION            Security ID:  704231AK5
Meeting Date: MAY 15, 2007   Meeting Type: Written Consent
Record Date:  MAY 15, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1     Elect Director - Ted S. Lodge             None      For        Shareholder
2     Elect Director - Eugene I. Davis          None      For        Shareholder


- --------------------------------------------------------------------------------

LOUISIANA-PACIFIC CORP

Ticker:       LPX            Security ID:  546347105
Meeting Date: MAY 3, 2007    Meeting Type: Annual
Record Date:  MAR 6, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director Lizanne C. Gottung         For       For        Management
1.2   Elect Director Dustan E. McCoy            For       For        Management
1.3   Elect Director Colin D. Watson            For       For        Management
2     Ratify Auditors                           For       For        Management


- --------------------------------------------------------------------------------

TITAN INTERNATIONAL, INC.

Ticker:       TWI            Security ID:  88830M102
Meeting Date: MAY 17, 2007   Meeting Type: Annual
Record Date:  MAR 20, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director Edward J. Campbell         For       For        Management
1.2   Elect Director Maurice M. Taylor, Jr.     For       For        Management
2     Approve Increase in Size of Board         For       For        Management
3     Elect Director J. Michael A. Akers        For       For        Management
4     Ratify Auditors                           For       For        Management


- --------------------------------------------------------------------------------

VODAFONE GROUP PLC

Ticker:       VOD            Security ID:  92857W100
Meeting Date: JUL 25, 2006   Meeting Type: Special
Record Date:  JUN 13, 2006

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1     TO APPROVE THE RETURN OF CAPITAL BY WAY   For       For        Management
      OF A B SHARE SCHEME AND SHARE
      CONSOLIDATION AND THE CONSEQUENTIAL
      AMENDMENT TO THE ARTICLES OF ASSOCIATION
2     TO RECEIVE THE REPORT OF THE DIRECTORS    For       For        Management
      AND FINANCIAL STATEMENTS
3.1   Elect  Director Sir John Bond             For       For        Management
3.2   Elect  Director Arun Sarin                For       For        Management
3.3   Elect  Director Thomas Geitner            For       For        Management
3.4   Elect  Director Dr Michael Boskin         For       For        Management
3.5   Elect  Director Lord Broers               For       For        Management
3.6   Elect  Director John Buchanan             For       For        Management
3.7   Elect  Director Andrew Halford            For       For        Management
3.8   Elect  Director Prof J. Schrempp          For       For        Management
3.9   Elect  Director Luc Vandevelde            For       For        Management
3.10  Elect  Director Philip Yea                For       For        Management
3.11  Elect  Director Anne Lauvergeon           For       For        Management
3.12  Elect  Director Anthony Watson            For       For        Management
4     TO APPROVE A FINAL DIVIDEND OF 3.87P PER  For       For        Management
      ORDINARY SHARE
5     TO APPROVE THE REMUNERATION REPORT        For       For        Management
6     Ratify Auditors                           For       For        Management
7     TO AUTHORISE THE AUDIT COMMITTEE TO       For       For        Management
      DETERMINE THE REMUNERATION OF THE
      AUDITORS
8     TO ADOPT NEW ARTICLES OF ASSOCIATION +    For       For        Management
9     TO AUTHORISE DONATIONS UNDER THE          For       For        Management
      POLITICAL PARTIES, ELECTIONS AND
      REFERENDUMS ACT 2000
10    TO RENEW AUTHORITY TO ALLOT SHARES UNDER  For       For        Management
      ARTICLE 16.2 OF THE COMPANY S ARTICLES OF
      ASSOCIATION
11    TO RENEW AUTHORITY TO DISAPPLY            For       For        Management
      PRE-EMPTION RIGHTS UNDER ARTICLE 16.3 OF
      THE COMPANY S ARTICLES OF ASSOCIATION +
12    TO AUTHORISE THE COMPANY S PURCHASE OF    For       For        Management
      ITS OWN SHARES (SECTION 166, COMPANIES
      ACT 1985) +


- --------------------------------------------------------------------------------

WASTE MANAGEMENT, INC.

Ticker:       WMI            Security ID:  94106L109
Meeting Date: MAY 4, 2007    Meeting Type: Annual
Record Date:  MAR 9, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1     Elect Director Pastora San Juan Cafferty  For       For        Management
2     Elect Director Frank M. Clark, Jr.        For       For        Management
3     Elect Director Patrick W. Gross           For       For        Management
4     Elect Director Thomas I. Morgan           For       For        Management
5     Elect Director John C. Pope               For       For        Management
6     Elect Director W. Robert Reum             For       For        Management
7     Elect Director Steven G. Rothmeier        For       For        Management
8     Elect Director David P. Steiner           For       For        Management
9     Elect Director Thomas H. Weidemeyer       For       For        Management
10    Ratify Auditors                           For       For        Management


- --------------------------------------------------------------------------------

WILLIAMS COMPANIES, INC., THE

Ticker:       WMB            Security ID:  969457100
Meeting Date: MAY 17, 2007   Meeting Type: Annual
Record Date:  MAR 26, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1     Elect Director Kathleen B. Cooper         For       For        Management
2     Elect Director William R. Granberry       For       For        Management
3     Elect Director Charles M. Lillis          For       For        Management
4     Elect Director William G. Lowrie          For       For        Management
5     Ratify Auditors                           For       For        Management
6     Approve Omnibus Stock Plan                For       For        Management
7     Approve Qualified Employee Stock Purchase For       For        Management
      Plan


- --------------------------------------------------------------------------------

WINDSTREAM CORP.

Ticker:       WIN            Security ID:  97381W104
Meeting Date: MAY 9, 2007    Meeting Type: Annual
Record Date:  MAR 16, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director Samuel E. Beall, III       For       For        Management
1.2   Elect Director Dennis E. Foster           For       For        Management
1.3   Elect Director Francis X. Frantz          For       For        Management
1.4   Elect Director Jeffery R. Gardner         For       For        Management
1.5   Elect Director Jeffrey T. Hinson          For       For        Management
1.6   Elect Director Judy K. Jones              For       For        Management
1.7   Elect Director William A. Montgomery      For       For        Management
1.8   Elect Director Frank E. Reed              For       For        Management
2     Approve Executive Incentive Bonus Plan    For       For        Management
3     Ratify Auditors                           For       For        Management
4     Stock Retention/Holding Period            Against   Against    Shareholder




====================== MFS HIGH YIELD OPPORTUNITIES FUND =======================


CHESAPEAKE ENERGY CORP.

Ticker:       CHK            Security ID:  165167107
Meeting Date: JUN 8, 2007    Meeting Type: Annual
Record Date:  APR 16, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director Frank Keating              For       For        Management
1.2   Elect Director Merrill A. Miller, Jr.     For       For        Management
1.3   Elect Director Frederick B. Whittemore    For       For        Management
2     Amend Omnibus Stock Plan                  For       For        Management
3     Amend Non-Employee Director Stock Option  For       For        Management
      Plan


- --------------------------------------------------------------------------------

FOUNDATION COAL HLDGS INC

Ticker:       FCL            Security ID:  35039W100
Meeting Date: MAY 17, 2007   Meeting Type: Annual
Record Date:  MAR 28, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director James F. Roberts           For       For        Management
1.2   Elect Director David I. Foley             For       For        Management
1.3   Elect Director Alex T. Krueger            For       For        Management
1.4   Elect Director P. Michael Giftos          For       For        Management
1.5   Elect Director Robert C. Scharp           For       For        Management
1.6   Elect Director William J. Crowley, Jr.    For       For        Management
1.7   Elect Director Joel Richards, III         For       For        Management
1.8   Elect Director Thomas V. Shockley, III    For       For        Management
2     Ratify Auditors                           For       For        Management
3     Other Business                            For       Against    Management


- --------------------------------------------------------------------------------

FRONTIERVISION OPERATING PARTNERS L.P.

Ticker:                      Security ID:  35921LAA3
Meeting Date: SEP 12, 2006   Meeting Type: Written Consent
Record Date:  NOV 28, 2005

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1     DEBTORS  FOURTH AMENDED JOINT PLAN OF     None      Did Not    Management
      REORGANIZATION UNDER CHAPTER 11 OF THE              Vote
      BANKRUPTCY CODE DATED NOVEMBER 21, 2005.


- --------------------------------------------------------------------------------

HUNTSMAN CORP

Ticker:       HUN            Security ID:  447011107
Meeting Date: MAY 3, 2007    Meeting Type: Annual
Record Date:  MAR 16, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director Nolan D. Archibald         For       For        Management
1.2   Elect Director H.W. Lichtenberger         For       Withhold   Management
1.3   Elect Director Richard A. Michaelson      For       For        Management
2     Ratify Auditors                           For       For        Management


- --------------------------------------------------------------------------------

ION  MEDIA NETWORKS, INC.

Ticker:       ION            Security ID:  704231AK5
Meeting Date: MAY 15, 2007   Meeting Type: Written Consent
Record Date:  MAY 15, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1     Elect Director - Ted S. Lodge             None      For        Shareholder
2     Elect Director - Eugene I. Davis          None      For        Shareholder


- --------------------------------------------------------------------------------

LOUISIANA-PACIFIC CORP

Ticker:       LPX            Security ID:  546347105
Meeting Date: MAY 3, 2007    Meeting Type: Annual
Record Date:  MAR 6, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director Lizanne C. Gottung         For       For        Management
1.2   Elect Director Dustan E. McCoy            For       For        Management
1.3   Elect Director Colin D. Watson            For       For        Management
2     Ratify Auditors                           For       For        Management


- --------------------------------------------------------------------------------

TITAN INTERNATIONAL, INC.

Ticker:       TWI            Security ID:  88830M102
Meeting Date: MAY 17, 2007   Meeting Type: Annual
Record Date:  MAR 20, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director Edward J. Campbell         For       For        Management
1.2   Elect Director Maurice M. Taylor, Jr.     For       For        Management
2     Approve Increase in Size of Board         For       For        Management
3     Elect Director J. Michael A. Akers        For       For        Management
4     Ratify Auditors                           For       For        Management


- --------------------------------------------------------------------------------

VODAFONE GROUP PLC

Ticker:       VOD            Security ID:  92857W100
Meeting Date: JUL 25, 2006   Meeting Type: Special
Record Date:  JUN 13, 2006

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1     TO APPROVE THE RETURN OF CAPITAL BY WAY   For       For        Management
      OF A B SHARE SCHEME AND SHARE
      CONSOLIDATION AND THE CONSEQUENTIAL
      AMENDMENT TO THE ARTICLES OF ASSOCIATION
2     TO RECEIVE THE REPORT OF THE DIRECTORS    For       For        Management
      AND FINANCIAL STATEMENTS
3.1   Elect  Director Sir John Bond             For       For        Management
3.2   Elect  Director Arun Sarin                For       For        Management
3.3   Elect  Director Thomas Geitner            For       For        Management
3.4   Elect  Director Dr Michael Boskin         For       For        Management
3.5   Elect  Director Lord Broers               For       For        Management
3.6   Elect  Director John Buchanan             For       For        Management
3.7   Elect  Director Andrew Halford            For       For        Management
3.8   Elect  Director Prof J. Schrempp          For       For        Management
3.9   Elect  Director Luc Vandevelde            For       For        Management
3.10  Elect  Director Philip Yea                For       For        Management
3.11  Elect  Director Anne Lauvergeon           For       For        Management
3.12  Elect  Director Anthony Watson            For       For        Management
4     TO APPROVE A FINAL DIVIDEND OF 3.87P PER  For       For        Management
      ORDINARY SHARE
5     TO APPROVE THE REMUNERATION REPORT        For       For        Management
6     Ratify Auditors                           For       For        Management
7     TO AUTHORISE THE AUDIT COMMITTEE TO       For       For        Management
      DETERMINE THE REMUNERATION OF THE
      AUDITORS
8     TO ADOPT NEW ARTICLES OF ASSOCIATION +    For       For        Management
9     TO AUTHORISE DONATIONS UNDER THE          For       For        Management
      POLITICAL PARTIES, ELECTIONS AND
      REFERENDUMS ACT 2000
10    TO RENEW AUTHORITY TO ALLOT SHARES UNDER  For       For        Management
      ARTICLE 16.2 OF THE COMPANY S ARTICLES OF
      ASSOCIATION
11    TO RENEW AUTHORITY TO DISAPPLY            For       For        Management
      PRE-EMPTION RIGHTS UNDER ARTICLE 16.3 OF
      THE COMPANY S ARTICLES OF ASSOCIATION +
12    TO AUTHORISE THE COMPANY S PURCHASE OF    For       For        Management
      ITS OWN SHARES (SECTION 166, COMPANIES
      ACT 1985) +


- --------------------------------------------------------------------------------

WASTE MANAGEMENT, INC.

Ticker:       WMI            Security ID:  94106L109
Meeting Date: MAY 4, 2007    Meeting Type: Annual
Record Date:  MAR 9, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1     Elect Director Pastora San Juan Cafferty  For       For        Management
2     Elect Director Frank M. Clark, Jr.        For       For        Management
3     Elect Director Patrick W. Gross           For       For        Management
4     Elect Director Thomas I. Morgan           For       For        Management
5     Elect Director John C. Pope               For       For        Management
6     Elect Director W. Robert Reum             For       For        Management
7     Elect Director Steven G. Rothmeier        For       For        Management
8     Elect Director David P. Steiner           For       For        Management
9     Elect Director Thomas H. Weidemeyer       For       For        Management
10    Ratify Auditors                           For       For        Management


- --------------------------------------------------------------------------------

WILLIAMS COMPANIES, INC., THE

Ticker:       WMB            Security ID:  969457100
Meeting Date: MAY 17, 2007   Meeting Type: Annual
Record Date:  MAR 26, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1     Elect Director Kathleen B. Cooper         For       For        Management
2     Elect Director William R. Granberry       For       For        Management
3     Elect Director Charles M. Lillis          For       For        Management
4     Elect Director William G. Lowrie          For       For        Management
5     Ratify Auditors                           For       For        Management
6     Approve Omnibus Stock Plan                For       For        Management
7     Approve Qualified Employee Stock Purchase For       For        Management
      Plan


- --------------------------------------------------------------------------------

WINDSTREAM CORP.

Ticker:       WIN            Security ID:  97381W104
Meeting Date: MAY 9, 2007    Meeting Type: Annual
Record Date:  MAR 16, 2007

#     Proposal                                  Mgt Rec   Vote Cast  Sponsor
1.1   Elect Director Samuel E. Beall, III       For       For        Management
1.2   Elect Director Dennis E. Foster           For       For        Management
1.3   Elect Director Francis X. Frantz          For       For        Management
1.4   Elect Director Jeffery R. Gardner         For       For        Management
1.5   Elect Director Jeffrey T. Hinson          For       For        Management
1.6   Elect Director Judy K. Jones              For       For        Management
1.7   Elect Director William A. Montgomery      For       For        Management
1.8   Elect Director Frank E. Reed              For       For        Management
2     Approve Executive Incentive Bonus Plan    For       For        Management
3     Ratify Auditors                           For       For        Management
4     Stock Retention/Holding Period            Against   Against    Shareholder




======================== MFS MUNICIPAL HIGH INCOME FUND ========================

NO PROXY VOTING RECORDS FOR THIS REPORITNG PERIOD.

========== END NPX REPORT


                                   SIGNATURES

Pursuant to the requirements of the Investment Company Act of 1940, the
registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.

Registrant: MFS SERIES TRUST III


By (Signature and Title)  MARIA F. DWYER*
                          ------------------------------------
                          Maria F. Dwyer,
                          Principal Executive Officer

Date: August 29, 2007


*By (Signature and Title) /s/ Susan S. Newton
                          ------------------------------------
                          Susan S. Newton, as attorney-in-fact

*    Executed by Susan S. Newton on behalf of Maria F. Dwyer pursuant to a Power
     of Attorney dated July 18, 2007. (1)

(1)  Incorporated by reference to MFS Series Trust XV (File Nos. 2-96738 and
     811-4253) Post-Effective Amendment No. 28 filed with the SEC via EDGAR on
     August 24, 2007 and to MFS Series Trust XIV (File No. 811-22033) Post-
     Effective Amendment No. 1 to be filed with the SEC via EDGAR on or about
     August 30, 2007.