EX-99.906CERT

Registrant Name: CGM Capital Development Fund

File Number: 811-00933

Registrant CIK Number: 0000060332

Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

The undersigned officers of the CGM Capital Development Fund (the
"Registrant"), with respect to the Registrant's Form N-CSR for the six-month
period ended June 30, 2005 as filed with the Securities and Exchange
Commission, each hereby certify that, to the best of such officer's knowledge:

    1. the Registrant's Form N-CSR fully complies with the requirements of
       section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

    2. the information contained in such Form N-CSR fairly presents, in all
       material respects, the financial condition and results of operations of
       the Registrant.

Date: August 22, 2005

/s/ Robert L. Kemp
Robert L. Kemp
President
Principal Executive Officer


Date: August 22, 2005

/s/ Jem A. Hudgins
Jem A. Hudgins
CFO & Treasurer
Principal Financial Officer

This certification is being furnished to the Securities and Exchange Commission
solely pursuant to 18 U.S.C. 1350 and is not being filed as part of the Form
N-CSR filed with the Commission.