Pusticamica Lake is a freshwater body of the southeastern portion of Eeyou Istchee James Bay (municipality), in Jamésie, in the administrative region of Nord-du-Québec, in the province of Quebec, in Canada.

This body of water extends into the townships of Duplessis, Mountain, Benoit and Ruette.

The hydrographic slope of Pusticamica Lake is accessible via route 113 which passes on the northwest side, between the lakes Waswanipi and Pusticamica; in addition, this forest road (North–south direction) from Desmaraisville goes south to serve the Wetetnagami River.

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

[2] The toponym "lac Pusticamica" was made official on December 5, 1968, by the Commission de toponymie du Québec, when it was created.