Two fire engines and 14 firefighters and officers were called to a fire at a flat in Brearley Close, Edgware.
Small parts of a ground floor flat was damaged by fire. Sadly, a woman was pronounced dead at the scene by London Ambulance Service.
The Brigade was called at 1410 and the fire was under control at 1458. Fire crews from Mill Hill and Hendon fire stations attended the scene.
The cause of the fire is under investigation.