Twelve fire engines and around 80 firefighters were called to a fire on West Cromwell Road in Earls Court.
Most of a flat on the first floor of a converted terraced house of four floors was damaged by the fire and another two flats were damaged by smoke. One man left the affected flat before the Brigade arrived. Firefighters wearing breathing apparatus rescued a further four women from other flats within the property. They have all been taken to hospital suffering smoke inhalation by London Ambulance Service crews.
Station Commander Clive Robinson, who was at the scene, said: "There was a significant amount of smoke issuing from the rear of the building, which prompted more than 20 calls to our Control Room."
The Brigade's 999 Control Officers took 24 calls to the blaze.
The Brigade was called at 0952 and the fire was under control by 1221. Fire crews from Hammersmith, Battersea, Chiswick, Paddington, North Kensington, Soho and surrounding fire stations were at the scene.
The cause of the fire has been recorded as undetermined.