Four fire engines and around 25 firefighters were called to a fire at a disused office block on Margery Street in Islington.
A small part of the ground floor of a two-storey building was damaged by fire. There were no reports of any injuries.
The Brigade was called at 1440 and the fire was under control by 1815. Fire crews from Shoreditch, Soho, Islington and Dowgate fire stations attended the scene.
The cause of the fire is under investigation by the Brigade and the Metropolitan Police Service.