Six fire engines and around 40 firefighters tackled a severe blaze in a launderette with flats above on Croydon High Street.
The Brigade's 999 Control took 47 calls to the fire and crews were faced with a fully developed fire when they arrived.
Firefighters rescued a man from the rear of the property via a ladder.
Four adults and one child left the building before the Brigade arrived. They were all treated by London Ambulance Service crews.
The fire destroyed the ground floor shop. The fire also damaged parts of the first and second floor.
The Brigade was called at 0058 and the fire was under control by 0234. Firefighters from Croydon and surrounding fire stations attended the scene. The cause of the fire is under investigation.