Lake Capichigamau is a freshwater body of the southern part of the Eeyou Istchee James Bay (municipality), in the region of Nord-du-Québec, in the province of Quebec, Canada.

The hydrographic slope of lake Capichigamau is accessible by a forest road (North-South direction) passing to the west of La Trève Lake and joining towards the South route 113 (linking Lebel-sur-Quévillon to Chibougamau).

The surface of Capichigamau Lake is usually frozen from early November to mid-May, however, safe ice circulation is generally from mid-November to mid-April.

The Lake Capichigamau outlet is located in the north and flows northward across the marsh zone to the mouth of Boissy Lake (elevation: 319 metres (1,047 ft)), which is crossed to the southwest by the Assinica River.

[2] The toponym "Lac Capichigamau" was formalized on December 5, 1968, by the Commission de toponymie du Québec when it was created.