Six fire engines and around 40 firefighters were called to a fire at a terraced house on Crestway in Wandsworth.
Part of the of ground floor and first floor were damaged by the blaze. Firefighters wearing breathing apparatus rescued a woman from the house and she was taken to hospital by London Ambulance Service crews.
The Brigade was called at 2226 and the fire was under control by 2327. Fire crews from Wandsworth, Richmond, Battersea, Hammersmith, Kingston and Fulham fire stations were in attendance.
The cause of the fire is under investigation by London Fire Brigade and the Metropolitan Police.