Lac Umisumisiwaw is a Lake located in Baie-James; Jamésie, Quebec.

• Latitude: 54° 18' 0'' North   (decimal: 54.3)
• Longitude: 75° 0' 56'' West   (decimal: -75.0155555)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Location: Baie-James; Jamésie
• Atlas of Canada Locator Map: Lac Umisumisiwaw
• GPS Coordinate Locator Map: Lac Umisumisiwaw Lat/Long