Lac Dernajou is a Lake located in Lac-Legendre; Matawinie, Quebec and has an elevation of 471 meters.

• Latitude: 46° 40' 23'' North   (decimal: 46.6730973)
• Longitude: 74° 18' 30'' West   (decimal: -74.3082176)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Elevation: 471 meters
• Location: Lac-Legendre; Matawinie
• Atlas of Canada Locator Map: Lac Dernajou
• GPS Coordinate Locator Map: Lac Dernajou Lat/Long