The Queue de Castor River (English: “Beaver’s tail River”) is a tributary of Gabriel Lake, flowing into the Eeyou Istchee James Bay (Municipality), in Jamésie, in the administrative region of Nord-du-Québec, in Quebec, Canada.

A logging camp has been established on the west bank of Ventadour Lake near a forest road.

The surface of the Beaver's Tail River is usually frozen from early November to mid-May, however Ice safety is usually from mid-November to mid-April.

The mouth of lake Beaucours is located at: From the mouth of the head lake, the "Queue de Castor River" flows on 23.6 kilometres (14.7 mi) according to the following segments: The “Queue de Castor River” flows into the bottom of a bay on the south shore of Gabriel Lake (Opawica River tributary) which flows through the North on 13.4 kilometres (8.3 mi).

The confluence of the "Queue de Castor River" with the Feuquières Lake is located at: At various times in history, this territory has been occupied by the Attikameks, the Algonquins and the Crees.