Six fire engines and around 40 firefighters were called to a fire at a block of flats on Pater Street in Kensington.
Part of a three-roomed basement flat in the five-storey block was alight. Firefighters wearing breathing apparatus rescued a woman from the affected flat. She was treated on scene for smoke inhalation and taken to hospital by London Ambulance Service crews.
The Brigade was called at just after 9am and the fire was under control by 10.27am Fire crews from Kensington, Hammersmith and Fulham fire stations were at the scene.
The cause of the fire is under investigation.