Donald MacKay Deacon (1920 - 2003) was a Canadian politician.

Deacon served in the Royal Canadian Artillery during World War II rising to the rank of Major. Following the war he was elected to the town council of Markham, Ontario rising to the position of Deputy Reeve. He was one of the founders of Markham Stouville Hospital. He entered business in the financial sector serving as chair of F.H. Deacon Hodgson Ltd and also served as president of the Canadian Club from 1968 to 1969.

Deacon was first elected to the Ontario legislature as a Liberal MPP in the 1967 Ontario election. He was re-elected in the 1971 Ontario election and represented the Toronto area riding of York Centre until he resigned from the legislature in March 1974.

In 1973, Deacon ran for the Ontario Liberal leadership when Robert Nixon indicated he was stepping aside. Nixon changed his mind and was re-elected leader with Deacon finishing in third place behind Nixon and Norman Cafik.

Decon moved to Prince Edward Island in 1981 and became president of the PEI Red Cross as well as a member of the board of Mount Allison University.

In 1987 he was made a Member of the Order of Canada and was promoted to Officer in 2003.

In 2003 he was presented with the Order of Prince Edward Island.

Reference

• "Donald M. Deacon, O.C., M.C., B.A. (http://www.gg.ca/Search/honours_descript_e.asp?type=2&id=411)." Office of the Secretary to the Governor General. Accessed on January 30, 2005.