Sweet Grass Creek is a tributary of the Yellowstone River, approximately 50 mi (80 km) long, in south central Montana in the United States.
It rises in the Gallatin National Forest, in the Crazy Mountains in eastern Park County. It flows northeast, into Sweet Grass County, then southeast, past Melville, and south, joining the Yellowstone 2 mi (3 km) northwest of Greycliff.
See List of Montana rivers
