Four fire engines and 21 firefighters and officers were called to a fire in a flat in Kersfield Road, Putney.
Part of a flat on the first floor of the building was damaged by fire.
The Brigade was called at 1022 and the fire was under control at 1127. Fire crews from Wandsworth, Fulham, Battersea and Hammersmith fire stations attended the scene.
The cause of the fire is under investigation.