Joseph Demers (November 11, 1861 – August 16, 1936) was a Canadian politician in the province of Quebec.Born in Sainte-Julie (Laurierville), Canada East, the son of Édouard Demers and Olympe Rousseau, Demers was educated in Sainte-Julie. He started clerking in 1877 until 1883 when he opened a general store in Thetford Mines. He was a councillor from 1890 till 1893, mayor from 1893 to 1895, and alderman from 1903 to 1905.