Belt Creek is a tributary of the Missouri River, approximately 80 mi (129 km) long, in western Montana in the United States.

It rises in the Lewis and Clark National Forest north of Big Baldy Mountain , in the Little Belt Mountains in western Judith Basin County. It flows northwest t hrough mountainous canyons past Monarch , then north past Armington and Belt. It joins the Missouri just downriver from the Great Falls of the Missouri , approximately 15 mi (25 km) northwest of Great Falls.

See List of Montana rivers