The Mistissini territory inhabits an area contained by the lakes and rivers draining into Mistassini Lake.

The southern part of the land is covered by a coniferous forest which contains white pine, poplar, small plants and mosses. The northern part of the land is covered by taiga forest.

We consider the land rich in fish, birds, big game and fur-bearing animals. We share the land with the following species of wildlife and waterfowl: moose, caribou, bear, beaver, otter, mink, weasel, muskrat, martin, fox, wolf, rabbit, partridge, parmigan, goose, ducks, Arctic loon, owls, and a variety of small birds.

The summers in Mistissini are very warm. The spring and fall are changing seasons marked by abundant rain fall. The winters are cold and dry with a lot of snow.