Lac de la Grosse Île is a Lake located in Rivière-Koksoak; Kativik, Quebec.

• Latitude: 55° 42' 57'' North   (decimal: 55.7159565)
• Longitude: 69° 17' 55'' West   (decimal: -69.2985370)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Location: Rivière-Koksoak; Kativik
• Atlas of Canada Locator Map: Lac de la Grosse Île
• GPS Coordinate Locator Map: Lac de la Grosse Île Lat/Long