Four fire engines and around 25 firefighters were called to a fire at a flat on Abbey Street in Bermondsey.
Household waste on a fifth floor balcony was alight. Three people left the building before the Brigade arrived. There were no reports of any injuries.
The Brigade was called at 0809 and the fire was under control by 0851. Fire crews from Dockhead, Old Kent Road, Dowgate, Whitechapel and Shadwell fire stations attended the scene.
The cause of the fire is under investigation.