The Otis General store caught fire a little after noon on Wednesday. Fire crews from several area departments raced to the scene and spotted flames rolling up the side of the building.
Ellsworth firefighters were first to arrive and managed to make short work of the spreading flames.
"From initial assessment, it looks like just the exterior of the building. Some minor damage to the interior, but it looks like it's limited to the outside of the building," Mariaville Fire Department Lt. Tom Bradswell.
Bradsell said the owners reported the fire and that everyone had evacuated by the time fire crews arrived.
A state fire marshal was expected to visit the scene to determine how the fire started.