The Saint-Pierre River is a tributary of the Mascouche River, flowing in the sector of "Saint-Janvier", in the city of Mirabel, in the region administrative Laurentides, in the southwest of Quebec at Canada.

This river runs eastwards an agricultural plain skirting the northern village of "Saint-Janvier".

Saint Pierre river rises between the Highway 15 and route 117, the northwest side of the village of Saint-Janvier. This source is located at:

• 5.9 kilometres (3.7 mi) north-east of the airport terminal to the Mirabel Airport;
• 14.6 kilometres (9.1 mi) north-west of rivière des Mille Îles;
• 6.6 kilometres (4.1 mi) west of the confluence of the Saint Pierre River.

Course of the river

From its source, the Saint-Pierre River flows on 9.4 kilometres (5.8 mi), according to the following segments:

• 0.8 kilometres (0.50 mi) north to the bridge of the route 117;
• 4.9 kilometres (3.0 mi) eastward, forming a detour to the north, up the road from "Côte Saint-Pierre";
• 3.7 kilometres (2.3 mi) to the south east, to the confluence of the river

The confluence of the Saint-Pierre River flows on the north bank of the Mascouche River, or 0.8 kilometres (0.50 mi) west of the city limits of Sainte-Thérèse-de-Blainville.

The place name "Rivière Saint-Pierre" is of Christian origin. Two tributaries of the north bank of the Mascouche River are designated "Saint-Pierre River."

The place name "Saint-Pierre River" was formalized on August 8, 1977 at the "Banque de noms de lieux" (Bank of place names) of Commission de toponymie du Québec (Quebec Geographical Names Board).

• Mirabel, a city
• Mascouche River, a stream
• Rivière des Mille Îles, a stream
• List of rivers of Quebec