Four fire engines and around 25 firefighters were called to reports of smoke issuing from a hotel on Catherine Grove in Greenwich.
Solar panels on the roof of the 10-storey building were involved in the fire. Electrical cabling was destroyed. There were no reports of any injuries.
The Brigade was called at 1205 and the incident was over by 1459. Fire crews from Greenwich, Deptford, New Cross and Lewisham fire stations were at the scene.
The cause of the fire is under investigation.