Two fire engines from Barnsley and Cudworth stations were called to a fire at a car wash centre on Wakefield Road in Smithies, Barnsley at 5:20am on Monday morning.
The car wash was well alight when crews arrived at the scene.
Firefighters wearing breathing apparatus tackled the fire with main jets.
Fire crews left the scene at 7:45am.
The fire is believed to have been started deliberately.