The rivière au Canard (in English: Duck River) is a watercourse crossing the municipality of Weedon, in the Le Haut-Saint-François Regional County Municipality (MRC), in the administrative region of Estrie, in Quebec, in Canada.

The neighboring hydrographic slopes of Lac au Canard are: The river has its source in Lac au Canard (length: 3.6 kilometres (2.2 mi); altitude: 340 metres (1,120 ft)) whose mouth is located on the south side.

This lake is located 1.1 kilometres (0.68 mi) southeast of Lake Nicolet, 3.3 kilometres (2.1 mi) south of the center of the village of Saints-Martyrs-Canadiens and 8.3 kilometres (5.2 mi) northwest of the center of the village of Saint-Gérard which is amalgamated into the municipality of Weedon.

From Lac au Canard, the Rivière au Canard flows for a distance of 13.9 kilometres (8.6 mi) in the following segments: The Canard River flows into Lake Louise, a lake crossed by the Saint-François River, near Weedon.

The toponym "Rivière au Canard" was made official on December 5, 1968, at the Commission de toponymie du Québec.