The rivière du Portage (in English: Portage Rivere) is a tributary of the Bécancour River which flows on the south shore of the St. Lawrence River.

The "rivière du Portage" flows in the municipalities of Saint-Valère and Daveluyville, in the Arthabaska Regional County Municipality (MRC), in the administrative region from Centre-du-Québec, to Quebec, to Canada.

The main hydrographic slopes of the "Portage river" are: The "Portage River" has its source in an agricultural area of the municipality of Saint-Valère, south of the Defoy hamlet (of Daveluyville), on the east side of route 261 and north of the Bulstrode River.

From its source, the Portage River flows over 12.5 kilometres (7.8 mi), especially in agricultural (or forest, in places) territory according to the following segments: The Portage River flows onto the south shore of the Bécancour River, just downstream from Portage Island and downstream from the village of Daveluyville.

The toponym "rivière du Portage" was made official on December 5, 1968, at Commission de toponymie du Québec.