Marquette Lake (French: Lac Marquette, pronounced [lak maʁkɛt]) is a freshwater body of the unorganized territory of Lac-Ashuapmushuan, Quebec in the Regional County Municipality (RCM) Le Domaine-du-Roy, north-west of Saguenay-Lac-Saint-Jean administrative region, in province of Quebec, in Canada.

Marquette Lake follows the western boundary (distance between 1.5 kilometres (0.93 mi) and 3.5 kilometres (2.2 mi)) outside (west side) of the boundary of the Ashuapmushuan Wildlife Reserve.

The Forest Road R0212 (East-West) passes the north side of Marquette Lake.

Other secondary forest roads serve the vicinity of the lake.

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