| Trois Saumons East River | |
| Pushpin Map: | Quebec |
| Subdivision Type1: | Country |
| Subdivision Name1: | Canada |
| Subdivision Type2: | Province |
| Subdivision Name2: | Quebec |
| Subdivision Type3: | Region |
| Subdivision Name3: | Chaudière-Appalaches |
| Subdivision Type4: | MRC |
| Subdivision Name4: | L'Islet Regional County Municipality |
| Source1: | Forest streams |
| Source1 Location: | Saint-Damase-de-L'Islet |
| Mouth: | Trois Saumons River |
| Mouth Location: | Saint-Aubert |
| Basin Size: | NaNkm (-2,147,483,648miles) |
| Tributaries Left: | (upstream) Ruisseau Creux, ruisseau à Bezeau |
| Tributaries Right: | (upstream) Ruisseau Lapointe |
The Trois Saumons East River(in French: Trois Saumons Est) river is a tributary of the east bank of the Trois Saumons River which flows to the south bank of the St. Lawrence River where it flows south-west of the village of Saint-Jean-Port-Joli and north-east of the village of L'Islet-sur-Mer.
The Trois Saumons Est river flows through the municipalities of Saint-Damase-de-L'Islet and Saint-Aubert, in the L'Islet Regional County Municipality, in the administrative region of Chaudière-Appalaches, in Quebec, in Canada.
The Trois Saumons Est river has its source on the eastern slope of the mountain designated "Le Pain de Sucre" which overlooks the eastern part of Trois Saumons lake (length: ; altitude:), located in the municipality of Saint-Aubert. This mountain stream-fed spring is located east of Trois Saumons lake, south-east of the south shore of St. Lawrence River, south of the center of the village of Saint-Damase-de-L'Islet.
From its source, the Trois Saumons Est River flows over .
The Trois Saumons Est River flows onto the east bank of the Trois Saumons River, west of Route 204. This confluence is located southeast of the center from the village of Saint-Aubert and to the south-east of the center of the village of Saint-Jean-Port-Joli.[1]
The toponym Rivière Trois Saumons Est was formalized on December 5, 1968, at the Commission de toponymie du Québec.[2]