Four fire engines and around 25 firefighters were called to a fire at a hotel on Park Lane in Mayfair.
Part of a room on the lower ground floor of a staffing block adjoining the eight-storey building and part of the ducting (extraction system) were damaged by the fire. There were no reports of any injuries.
The Brigade was called at 3.15pm and the fire was under control by 5.02pm.
Fire crews from Chelsea, Soho and Paddington fire stations were at the scene.
The cause of the fire is under investigation.