Four fire engines and around 25 firefighters were called to a fire at a house on Sydney Road in Sutton.
The ground floor of the end of terrace house was destroyed by the fire and most of the first floor was damaged. One man was taken to hospital, where he sadly later died. Another two men were treated on scene for smoke inhalation by London Ambulance Service crews.
The Brigade's 999 Control Officers took 12 calls to the blaze.
The Brigade was called at 1911 and the fire was under control by 2118. Fire crews from Sutton, Wallington and Mitcham fire stations were at the scene.
The cause of the fire is under investigation.