Isidore Proulx (March 13, 1840 – July 28, 1904) was an Ontario farmer, merchant and political figure. He represented Prescott in the Canadian House of Commons, as a Liberal Party member from 1891 to 1904.Proulx was born in Saint-Hermas, Lower Canada in 1840, and he served as clerk for Saint-Hermas for 20 years. In 1861, he married Philomène Lalande. Proulx ran unsuccessfully in the riding of Deux-Montagnes for a seat in the Quebec legislative assembly in 1874.