Fifteen fire engines and around 100 firefighters tackled a fire on Electric Lane near Brixton Market.
The ground floor of a two-storey storage warehouse was destroyed by the fire and part of the first floor and roof were damaged. Around 50 people left the building before the Brigade arrived. There were no reports of any injuries.
The Brigade's 999 Control Officers took 53 calls to the blaze.
The Brigade was called at 2058 and the fire was under control by 0030. Fire crews from Clapham, West Norwood, Peckham, Old Kent Road, Chelsea and surrounding fire stations were at the scene.
The cause of the fire on Electric Lane near Brixton Market is believed to have been accidental. However, due to the extent of the damage fire investigators have recorded the exact cause as undetermined.