Busby is a census-designated place (CDP) in Big Horn County, Montana, United States. It is on the Northern Cheyenne reservation. The population was 745 at the 2010 census. The town is about twenty miles northeast of the site of the Battle of the Rosebud and the associated Rosebud Battlefield State Park, where General George Crooks forces encountered Sioux and Cheyenne forces led by Crazy Horse.
The town is named for postmaster Sheridan Busby. The post office was established in 1904.
Trader W. P. Moncure erected the Two Moons Monument at Busby in 1936.