The Bras Coupé Lake (French: Lac du Bras Coupé) is a freshwater body of the southern part of Eeyou Istchee James Bay (municipality), in the administrative region of Nord-du-Québec, in the province of Quebec, in Canada.

The area of Bras Coupé Lake extends entirely into the townships of Lescure, in the territory of the Eeyou Istchee James Bay (municipality) regional government, south of Chapais, Quebec.

From there, the current of the Opawica River flows South-west over 10.9 kilometres (6.8 mi) to the eastern shore of Doda Lake.

This mouth is located at: The main hydrographic slopes near Bras Coupé Lake are: This hydronym was formalized in 1935 by the Quebec Geography Committee.

This name reflects the particular shape of this river arm intersected by four large peninsulas downstream of the Lac des Vents.