Lac La Martre, is the third largest lake in the Northwest Territories, Canada. It is located approximately northwest of the territorial capital of Yellowknife. The Tà Âñèchë community of Whatì (formerly called Lac La Martre) is located on the east shore of Lac La Martre.
The lake is located on a main north/south bird migration route. Hundreds of thousands of ducks, geese and other migratory bird species gather to feed in the marshes.
Whatì, a small First Nations community with a population of 470, is located on the shores of the lake.