Isaac Clemens (January 21 1815 – September 24 1880) was an Ontario farmer and political figure. He represented Waterloo South in the Legislative Assembly of Ontario as a Liberal member from 1867 to 1874. He was born near Speedsville in Waterloo County in 1815, a descendant of Pennsylvania Dutch settlers. He served as reeve of Waterloo Township for 10 years and as county warden.
