Four fire engines and 21 firefighters and officers were called to a fire at a block of flats in Oliver Road, Leyton.
Half of a second floor flat was damaged by fire. One woman was rescued by firefighters wearing breathing apparatus and led to safety via an internal staircase.
The Brigade was called at 1007 and the fire was under control at 1115. Fire crews from Leyton, Leytonstone and Walthamstow fire stations attended the scene.
The cause of the fire is under investigation.