William Dynes (1849 – 1935) was an Ontario farmer and political figure.
He represented Dufferin in the Legislative Assembly of Ontario from 1894 to 1898 as a Patrons of Industry member.
Dynes served as reeve for Mono and was the first postmaster for Granger.
He was also president of the Dufferin Mutual Fire Insurance Company.
Dynes died in Victoria, British Columbia.