Four fire engines and around 25 firefighters were called to a fire at an industrial unit on Eskdale Road in Uxbridge.
A small part of a single-storey unit was damaged by the fire. There were no reports of any injuries.
The Brigade was called at 0238 and the fire was under control by 0340. Fire crews from Hillingdon, Hayes and Heathrow fire stations attended the scene.
The cause of the fire is under investigation.