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

• Latitude: 49° 7' 38'' North   (decimal: 49.1272222)
• Longitude: 69° 42' 59'' West   (decimal: -69.7163889)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Location: Lac-au-Brochet; La Haute-Côte-Nord
• Atlas of Canada Locator Map: Lac Armstrong
• GPS Coordinate Locator Map: Lac Armstrong Lat/Long