The Mitis River is a salmon river in the Bas-Saint-Laurent region of Quebec, Canada. It flows to the south shore of the Saint Lawrence River. There are two hydroelectric dams on the river at a point where a waterfall used to prevent salmon from going further upstream. A system to capture and transport salmon upstream was installed in 1965, and the river now has a healthy salmon population along its whole length.

The Bas-Saint-Laurent, is an administrative region of Quebec located along the south shore of the lower Saint Lawrence River in Quebec. The river widens at this place, later becoming a bay that discharges into the Atlantic Ocean and is often nicknamed "Bas-du-Fleuve" (Lower-River). The region is formed by eight regional county municipalities and 114 municipalities. In the south, it borders Maine of the United States, and the Canadian New Brunswick and the regions of Chaudière-Appalaches and Gaspésie–Îles-de-la-Madeleine.