Four fire engines and 21 firefighters and officers were called to a fire at a restaurant with offices above in Beauchamp Place in Knightsbridge.
Part of the basement of the restaurant was damaged by fire.
Approximately 90 people were evacuated from the restaurant by the Brigade as a precaution. One man suffered smoke inhalation and was taken to hospital by London Ambulance Service crews.
The Brigade was called at 2240 and the fire was under control at 2341. Fire crews from Lambeth, Soho and Battersea fire stations attended the scene.
The cause of the fire is under investigation.