Four fire engines and around 25 firefighters were called to a fire at a house converted into flats in Chalfont Road in Edmonton.
The staircase from ground to first floor level was destroyed by fire. Part of a flat on the first floor was also damaged by fire.
One woman was rescued from the first floor by crews wearing breathing apparatus but sadly she was pronounced dead at the scene.
The Brigade was called at 2236 and the fire was under control at 2358. Fire crews from Edmonton and Tottenham fire stations attended the scene.
The cause of the fire is under investigation by the Brigade and Metropolitan Police Service.