Louis Philippe Demers (September 16, 1863 – November 3, 1951) was a Canadian lawyer, professor, and politician.

Born in St-Georges d'Henryville, Canada East, the son of Alexis-Louis Demers, a Quebec politician, and Marie Goyette.

Demers was educated at the College of St. Hyacinthe, Quebec and Laval University, Montreal.

As a lawyer, he was the head of the firm of Demer and DeLorimier in Montreal.

He was a Professor of Commercial Law at Laval University, Montreal.