Lac Perdu is a Lake located in Mont-Valin; Le Fjord-du-Saguenay, Quebec.

• Latitude: 50° 13' 55'' North   (decimal: 50.2320109)
• Longitude: 70° 33' 55'' West   (decimal: -70.5653865)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Location: Mont-Valin; Le Fjord-du-Saguenay
• Atlas of Canada Locator Map: Lac Perdu
• GPS Coordinate Locator Map: Lac Perdu Lat/Long