Four fire engines and around 25 firefighters tackled a canal boat fire on Packet Boat Lane in Uxbridge.
Around half of the boat was damaged by the fire. One man was treated on scene by London Ambulance Service.
The Brigade was called at 1107 and crews from Hillingdon, Hayes, Heathrow and Northolt fire stations attended the scene. The fire was extinguished by 1228.
The fire is believed to have been accidental and was caused by the failure of an extension lead.