Three fire crews were dispatched to the Crow Head Start Center Sunday evening.
Crow Bureau of Indian Affairs Forestry, Crow Tribal Volunteer Fire Department and Big Horn County Fire Department all responded to the blaze in the abandoned building, which started around 6:20 p.m.
The building was previously condemned, so the water, electricity and gas were all disconnected, said Crow Tribal Chairman Frank Whiteclay.
Crow crews will start clean up after the blaze goes out.
Traffic is blocked in front of the head start center and crowds are asked to keep their distance.