Lac O is a Lake located in Lac-au-Brochet; La Haute-Côte-Nord, Quebec.

• Latitude: 48° 33' 28'' North   (decimal: 48.5577778)
• Longitude: 69° 36' 26'' West   (decimal: -69.6072222)
• Topography Feature Category: Lake
• Geographical Feature: Étang
• Canadian Province/Territory: Quebec
• Location: Lac-au-Brochet; La Haute-Côte-Nord
• Atlas of Canada Locator Map: Lac O
• GPS Coordinate Locator Map: Lac O Lat/Long