The Lake Masketsi is located in the unorganized territory of Lac-Masketsi, in the Mekinac Regional County Municipality, in Mauricie, in Quebec, in Canada.

Landfill located in the southeastern part of the lake empties after 500 meters further south in the "Little Lake-Masketsi".

Masketsi Lake and Little Lake-Masketsi, each comprise a dam at their mouths, for the purpose of resort and recrotouristics activities.

The dam downstream is the one of "Little lake Masketsi"[1] which was built initially in 1921 for the operation of Audy sawmill, north of Hervey-Jonction.

The east side of the lake has mountains that required extensive blasting during construction of the railway.