Moose Mountain Creek is a river in the province of Saskatchewan, Canada. Its source is the Chapleau Lakes near Montmartre and it is a tributary of the Souris River, which, in turn, is a tributary of the Assiniboine River. The whole system is part of the Red River watershed, which is part of the Hudson Bay drainage basin and in a region called the Prairie Pothole Region of North America, which extends throughout three Canadian provinces and five U.S. states. It is also within Palliser's Triangle and the Great Plains ecoregion.