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                                 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

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

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

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

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

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                      Date of fiscal year end: January 31

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             Date of reporting period: July 1, 2010 - June 30, 2011

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ITEM 1.  PROXY VOTING RECORD.

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

ICA File Number: 811-02794
Reporting Period: 07/01/2010 - 06/30/2011
MFS Series Trust III









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


ACCURIDE CORPORATION

Ticker:       ACW            Security ID:  00439T107
Meeting Date: NOV 18, 2010   Meeting Type: Special
Record Date:  OCT 13, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     Approve Reverse Stock Split             For       For          Management
2     Adjourn Meeting                         For       For          Management


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ACCURIDE CORPORATION

Ticker:       ACW            Security ID:  00439TAA5
Meeting Date: NOV 18, 2010   Meeting Type: Special
Record Date:  OCT 13, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     Approve Reverse Stock Split             For       For          Management
2     Adjourn Meeting                         For       For          Management


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ACCURIDE CORPORATION

Ticker:       ACW            Security ID:  00439T206
Meeting Date: APR 26, 2011   Meeting Type: Annual
Record Date:  MAR 11, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director Keith E. Busse           For       Withhold     Management
1.2   Elect Director Richard F. Dauch         For       For          Management
1.3   Elect Director Benjamin C. Duster, IV   For       Withhold     Management
1.4   Elect Director Robert J. Kelly          For       Withhold     Management
1.5   Elect Director William M. Lasky         For       For          Management
1.6   Elect Director Stephen S. Ledoux        For       For          Management
1.7   Elect Director John W. Risner           For       For          Management
2     Ratify Auditors                         For       For          Management
3     Approve Omnibus Stock Plan              For       For          Management
4     Advisory Vote to Ratify Named Executive For       Against      Management
      Officers' Compensation
5     Advisory Vote on Say on Pay Frequency   One Year  One Year     Management


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AMERICAN MEDIA OPERATIONS INC

Ticker:                      Security ID:  02744RAR8
Meeting Date: NOV 15, 2010   Meeting Type: Written Consent
Record Date:  NOV 01, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan                      None      For          Management


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AMERICAN MEDIA OPERATIONS INC

Ticker:                      Security ID:  02744RAT4
Meeting Date: NOV 15, 2010   Meeting Type: Written Consent
Record Date:  NOV 01, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan                      None      For          Management


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AMERISTAR CASINOS, INC.

Ticker:       ASCA           Security ID:  03070Q101
Meeting Date: JUN 15, 2011   Meeting Type: Annual
Record Date:  APR 18, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director Larry A. Hodges          For       For          Management
1.2   Elect Director Luther P. Cochrane       For       For          Management
2     Ratify Auditors                         For       For          Management
3     Amend Omnibus Stock Plan                For       Against      Management
4     Advisory Vote to Ratify Named Executive For       For          Management
      Officers' Compensation
5     Advisory Vote on Say on Pay Frequency   Three     One Year     Management
                                              Years


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GENERAL MOTORS CO.

Ticker:       GM             Security ID:  370442BS3
Meeting Date: FEB 11, 2011   Meeting Type: Written Consent
Record Date:  DEC 07, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan, As Further          For       For          Management
      Described In The Consent Solicitation
      Package


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NORTEK, INC.

Ticker:       NTKS           Security ID:  656559309
Meeting Date: NOV 09, 2010   Meeting Type: Annual
Record Date:  SEP 23, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director John T. Coleman          For       For          Management
1.2   Elect Director Thomas A. Keenan         For       For          Management
1.3   Elect Director J. David Smith           For       For          Management
2     Ratify Auditors                         For       For          Management
3     Approve Omnibus Stock Plan              For       For          Management


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QUAD/GRAPHICS, INC.

Ticker:       QUAD           Security ID:  747301109
Meeting Date: MAY 16, 2011   Meeting Type: Annual
Record Date:  MAR 18, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director William J. Abraham, Jr.  For       Withhold     Management
1.2   Elect Director Mark A. Angelson         For       Withhold     Management
1.3   Elect Director Douglas P. Buth          For       For          Management
1.4   Elect Director Christopher B. Harned    For       Withhold     Management
1.5   Elect Director Betty Ewens Quadracci    For       Withhold     Management
1.6   Elect Director J. Joel Quadracci        For       Withhold     Management
1.7   Elect Director Thomas O. Ryder          For       For          Management
1.8   Elect Director John S. Shiely           For       For          Management
2     Advisory Vote to Ratify Named Executive For       For          Management
      Officers' Compensation
3     Advisory Vote on Say on Pay Frequency   Three     One Year     Management
                                              Years
4     Approve Omnibus Stock Plan              For       For          Management




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


ACCURIDE CORPORATION

Ticker:       ACW            Security ID:  00439T107
Meeting Date: NOV 18, 2010   Meeting Type: Special
Record Date:  OCT 13, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     Approve Reverse Stock Split             For       For          Management
2     Adjourn Meeting                         For       For          Management


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ACCURIDE CORPORATION

Ticker:       ACW            Security ID:  00439TAA5
Meeting Date: NOV 18, 2010   Meeting Type: Special
Record Date:  OCT 13, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     Approve Reverse Stock Split             For       For          Management
2     Adjourn Meeting                         For       For          Management


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ACCURIDE CORPORATION

Ticker:       ACW            Security ID:  00439T206
Meeting Date: APR 26, 2011   Meeting Type: Annual
Record Date:  MAR 11, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director Keith E. Busse           For       Withhold     Management
1.2   Elect Director Richard F. Dauch         For       For          Management
1.3   Elect Director Benjamin C. Duster, IV   For       Withhold     Management
1.4   Elect Director Robert J. Kelly          For       Withhold     Management
1.5   Elect Director William M. Lasky         For       For          Management
1.6   Elect Director Stephen S. Ledoux        For       For          Management
1.7   Elect Director John W. Risner           For       For          Management
2     Ratify Auditors                         For       For          Management
3     Approve Omnibus Stock Plan              For       For          Management
4     Advisory Vote to Ratify Named Executive For       Against      Management
      Officers' Compensation
5     Advisory Vote on Say on Pay Frequency   One Year  One Year     Management


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AMERICAN MEDIA OPERATIONS INC

Ticker:                      Security ID:  02744RAR8
Meeting Date: NOV 15, 2010   Meeting Type: Written Consent
Record Date:  NOV 01, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan                      None      For          Management


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AMERICAN MEDIA OPERATIONS INC

Ticker:                      Security ID:  02744RAT4
Meeting Date: NOV 15, 2010   Meeting Type: Written Consent
Record Date:  NOV 01, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan                      None      For          Management


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AMERISTAR CASINOS, INC.

Ticker:       ASCA           Security ID:  03070Q101
Meeting Date: JUN 15, 2011   Meeting Type: Annual
Record Date:  APR 18, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director Larry A. Hodges          For       For          Management
1.2   Elect Director Luther P. Cochrane       For       For          Management
2     Ratify Auditors                         For       For          Management
3     Amend Omnibus Stock Plan                For       Against      Management
4     Advisory Vote to Ratify Named Executive For       For          Management
      Officers' Compensation
5     Advisory Vote on Say on Pay Frequency   Three     One Year     Management
                                              Years


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GENERAL MOTORS CO.

Ticker:       GM             Security ID:  370442BS3
Meeting Date: FEB 11, 2011   Meeting Type: Written Consent
Record Date:  DEC 07, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan, As Further          For       For          Management
      Described In The Consent Solicitation
      Package


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NORTEK, INC.

Ticker:       NTKS           Security ID:  656559309
Meeting Date: NOV 09, 2010   Meeting Type: Annual
Record Date:  SEP 23, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director John T. Coleman          For       For          Management
1.2   Elect Director Thomas A. Keenan         For       For          Management
1.3   Elect Director J. David Smith           For       For          Management
2     Ratify Auditors                         For       For          Management
3     Approve Omnibus Stock Plan              For       For          Management


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OWENS-ILLINOIS, INC.

Ticker:       OI             Security ID:  690768403
Meeting Date: MAY 05, 2011   Meeting Type: Annual
Record Date:  MAR 07, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director Peter S. Hellman         For       For          Management
1.2   Elect Director Anastasia D. Kelly       For       For          Management
1.3   Elect Director John J. Mcmackin, Jr.    For       For          Management
1.4   Elect Director Hugh H. Roberts          For       For          Management
2     Ratify Auditors                         For       For          Management
3     Advisory Vote to Ratify Named Executive For       For          Management
      Officers' Compensation
4     Advisory Vote on Say on Pay Frequency   Three     One Year     Management
                                              Years


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QUAD/GRAPHICS, INC.

Ticker:       QUAD           Security ID:  747301109
Meeting Date: MAY 16, 2011   Meeting Type: Annual
Record Date:  MAR 18, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director William J. Abraham, Jr.  For       Withhold     Management
1.2   Elect Director Mark A. Angelson         For       Withhold     Management
1.3   Elect Director Douglas P. Buth          For       For          Management
1.4   Elect Director Christopher B. Harned    For       Withhold     Management
1.5   Elect Director Betty Ewens Quadracci    For       Withhold     Management
1.6   Elect Director J. Joel Quadracci        For       Withhold     Management
1.7   Elect Director Thomas O. Ryder          For       For          Management
1.8   Elect Director John S. Shiely           For       For          Management
2     Advisory Vote to Ratify Named Executive For       For          Management
      Officers' Compensation
3     Advisory Vote on Say on Pay Frequency   Three     One Year     Management
                                              Years
4     Approve Omnibus Stock Plan              For       For          Management


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SANDRIDGE ENERGY, INC.

Ticker:       SD             Security ID:  80007P307
Meeting Date: JUL 16, 2010   Meeting Type: Special
Record Date:  JUN 16, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     Issue Shares in Connection with         For       For          Management
      Acquisition
2     Increase Authorized Common Stock        For       For          Management


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SANDRIDGE ENERGY, INC.

Ticker:       SD             Security ID:  80007P307
Meeting Date: JUN 03, 2011   Meeting Type: Annual
Record Date:  APR 06, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director Roy T. Oliver            For       Did Not Vote Management
1.2   Elect Director Tom L. Ward              For       Did Not Vote Management
2     Ratify Auditors                         For       Did Not Vote Management
3     Amend Omnibus Stock Plan                For       Did Not Vote Management
4     Advisory Vote to Ratify Named Executive For       Did Not Vote Management
      Officers' Compensation
5     Advisory Vote on Say on Pay Frequency   Three     Did Not Vote Management
                                              Years




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


SMURFIT-STONE CONTAINER CORPORATION

Ticker:       SSCC           Security ID:  83272A104
Meeting Date: MAY 27, 2011   Meeting Type: Special
Record Date:  APR 08, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     Approve Merger Agreement                For       For          Management
2     Adjourn Meeting                         For       For          Management


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SUMNER COUNTY TENN

Ticker:                      Security ID:  86642PDF1
Meeting Date: JUN 16, 2011   Meeting Type: Written Consent
Record Date:  APR 26, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     The Plan                                None      For          Management


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SUMNER COUNTY TENN

Ticker:                      Security ID:  86642PDK0
Meeting Date: JUN 16, 2011   Meeting Type: Written Consent
Record Date:  APR 26, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     The Plan                                None      For          Management


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WEST POINT VIRGINIA INDUS DEV AUTH SOLID WASTE

Ticker:                      Security ID:  955489AE9
Meeting Date: MAR 22, 2011   Meeting Type: Written Consent
Record Date:  FEB 15, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan                      For       For          Management
2     Opt Out Release                         For       For          Management


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WEST POINT VIRGINIA INDUS DEV AUTH SOLID WASTE

Ticker:                      Security ID:  955489AF6
Meeting Date: MAR 22, 2011   Meeting Type: Written Consent
Record Date:  FEB 15, 2011

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan                      For       For          Management
2     Opt Out Release                         For       For          Management


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YONKERS N Y INDL

Ticker:                      Security ID:  986083BJ1
Meeting Date: SEP 03, 2010   Meeting Type: Written Consent
Record Date:  MAY 27, 2010

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     Undersigned Hereby Approves To Waive    For       For          Management
      Long-term Debt Service Coverage Ratio
      For St. John's Riverside Hospital For
      Fiscal Year 2009, Consents To And
      Directs The Trustee To Waive Such
      Longterm Debt Service Coverage Ratio &
      To Execute First Supplemental

========== 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. DIORIODWYER*
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                          Maria F. DiOrioDwyer,
                          Principal Executive Officer

Date: August 12, 2011

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

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*    Executed by Susan S. Newton on behalf of Maria F. DiOrioDwyer pursuant to
     a Power of Attorney dated October 26, 2010. (1)

(1)  Incorporated by reference to MFS Series Trust XIII (File Nos. 2-74959
     and 811-3327) Post-Effective Amendment No. 45 filed with the SEC via EDGAR
     on March 10, 2011.