Six fire engines and around 40 firefighters tackled a maisonette fire on Lensbury Way in Abbey Wood.
A split-level maisonette on the first and second floors of the building was destroyed by fire. Half of a further three-roomed flat on the first floor was also damaged by the blaze. Nine people left the property before the Brigade arrived. There were no reports of any injuries.
The Brigade's 999 Control Officers took 11 calls to the blaze.
The Brigade was called at 1347 and the fire was under control by 1508. Fire crews from Plumstead, Greenwich, Deptford, Brixton, Lee Green and Eltham fire stations attended the scene.
The cause of the fire is under investigation.