William Rabb Beatty (June 11, 1851 – February 8, 1905) was an Ontario businessman and political figure. He represented Parry Sound in the Legislative Assembly of Ontario as a Liberal-Patrons of Industry member from 1894 to 1898 and as a Liberal from 1898 to 1902.

He was the manager for the Beatty Line, a steamship company operating on the Great Lakes. His brother Walter Beatty also served in the provincial assembly. Beatty lived in Parry Sound.

• The Canadian parliamentary companion, 1897 JA Gemmill
• Ontario Legislative Assembly parliamentary history