Firefighters tackled a flat fire on Neville Gill Close in Wandsworth.
Part of a five-roomed flat on the seventh floor of a residential block was damaged by fire. Two adults and a child were treated on scene by London Ambulance Service crews after suffering from slight smoke inhalation.
The Brigade was called at 0058 and the fire was under control by 0143. Five fire engines and around 35 firefighters from Wandsworth, Battersea, Tooting and Fulham fire stations attended the scene.
The cause of the fire is under investigation.