Six fire engines and around 40 firefighters tackled a blaze on the balcony of block of flats on Barking Road in Canning Town.
Firefighters contained the fire to the third floor balcony and stopped the fire spreading to the surrounding flats. The resident was led to safety by fire crews. He was suffering slight smoke inhalation and treated at the scene by London Ambulance Service crews.
All other residents remained safely in their own flats.
The cause of the fire is believed to be the unsafe disposal of a cigarette on the balcony.
A London Fire Brigade spokesperson said: “We’d rather you didn’t smoke at all, but if you are a smoker, it’s absolutely vital you ensure your cigarette is completely out when you’ve finished smoking it.
“If you don’t, you risk causing a fire which could not only destroy your home, but also cost you your life.”
The Brigade was called at 0204 and the fire was under control by 0309. Firefighters from Poplar, Plaistow, Stratford, Millwall, East Ham and Shadwell fire stations.