Four fire engines and around 25 firefighters were called to a fire on Brickfield Lane in Hayes.
Part of a single storey derelict building was damaged by fire. There were no reports of any injuries.
The Brigade was called at 1840 and the fire was under control by 2057. Fire crews from Hayes, Heathrow and Hillingdon fire stations attended the scene.
The cause of the fire is under investigation by the Brigade and the Metropolitan Police Service.