Four fire engines and around 20 firefighters and officers were called to a fire at a shop with flats above in Holloway Road in Islington.
The ducting from ground to roof level and part of the ground floor shop were damaged by fire.
One man left the property before the arrival of the Brigade and one man was led to safety by firefighters wearing breathing apparatus. There are no reports of any injuries.
The Brigade was called at 1302 and the fire was under control at 1418. Fire crews from Holloway, Islington, Kentish Town and Shoreditch fire stations attended the scene.
The cause of the fire is under investigation.