Four fire engines and around 25 firefighters were called to a fire at a visitors' centre on Albert Road in South Norwood.
Most of the roof of the single-storey building was damaged by the fire and the rest of the building was damaged by smoke. There were no reports of any injuries.
The Brigade was called at 1913 and the fire was under control by 2144. Fire crews from Woodside, Beckenham and West Norwood fire stations were at the scene.
The cause of the fire is under investigation by the Brigade and the Metropolitan Police Service.