Four fire engines and around 25 firefighters tackled a fire at a block of flats on Clapham Park Road in Clapham.
Half of a ground floor flat was damaged by the fire. Six people from a neighbouring flat left the building before the Brigade arrived. There are no reports of any injuries.
The Brigade was called at 1919 and the incident was over for firefighters at 2006. Firefighters from Clapham, Brixton, Battersea and Tooting fire stations attended the scene.
The cause of the fire is under investigation by the Brigade and the Metropolitan Police Service.