The Rivière du Loup is a river in southeastern Quebec which empties into the Saint Lawrence River at the city of Rivière-du-Loup, Quebec.
There is a hydroelectric plant on the river near the city.
The river's name means Wolf River in French and may have come from a native tribe known as "Les Loups" or from the many seals, known in French as loup-marin, once found at the river's mouth.