Lac Sousni is a Lake located in Rivière-Mistassini; Maria-Chapdelaine, Quebec and has an elevation of 605 meters.

• Latitude: 49° 54' 12'' North   (decimal: 49.9033333)
• Longitude: 72° 17' 35'' West   (decimal: -72.2930556)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Elevation: 605 meters
• Location: Rivière-Mistassini; Maria-Chapdelaine
• Atlas of Canada Locator Map: Lac Sousni
• GPS Coordinate Locator Map: Lac Sousni Lat/Long