The London Fire Brigade was called to Thomas Lane at around 3.45am today (January 12).
The flames destroyed part of a flat on the seventh floor of a nine-storey block.
The man was rescued from the three-roomed flat by crews wearing breathing apparatus and suffered from smoke inhalation.
35 firefighters from Lewisham, Forest Hill, Greenwich, Lee Green and Deptford fire stations brought the fire under control by 5am.
The cause of the fire is under investigation.
