The Rivière Ouiatchouaniche is a 65.7-kilometer (40.8-mile) river flowing through the Saguenay–Lac-Saint-Jean region of Quebec, Canada. Originating at Quentin Lake in the unorganized territory of Lac-Ashuapmushuan at an elevation of 301 meters (988 feet), the river descends through forested and agricultural landscapes before emptying into Lac Saint-Jean at Roberval, at an elevation of 101 meters (331 feet). This elevation drop of 200 meters over its length creates a river with genuine character and variety, making it an appealing destination for anglers targeting multiple species. The river flows through the Le Domaine-du-Roy Regional County Municipality, passing through the municipality of Sainte-Hedwidge and the city of Roberval on its way to Lac Saint-Jean, which itself drains into the Saguenay River system.