Eight fire engines and around 60 firefighters were called to a fire at a terraced house converted into flats on Star Street in Paddington.
Most of a basement flat was damaged by the fire. One man left the affected flat before the Brigade arrived. Firefighters rescued another man from an adjacent property. He was suffering smoke inhalation and was assessed at the scene but was not taken to hospital.
The Brigade's 999 Control Officers took 12 calls to the fire.
The Brigade was called at 1719 and the fire was under control at 1831. Fire crews from Paddington, Euston, Kensington, North Kensington and surrounding fire stations were at the scene.
The cause of the fire is under investigation by the Brigade and the Metropolitan Police Service.