Six fire engines and 35 firefighters and officers were called to a fire at a caravan site off Bashley Road in Park Royal.
A refuse area was destroyed by fire.
Station Manager Andy Walton said:
"When firefighters arrived it was quickly established that the fire was contained to a pile of refuse behind a wall adjacent to caravans. Fire crews worked with members of the travelling community to gain full access to the fire and worked hard to prevent the fire spreading."
The Brigade was called at 1955 and the fire was under control at 2238. Fire crews from Park Royal, Acton, Willesden, North Kensington and Chiswick fire stations attended the scene.
The cause of the fire is believe to have been caused by a firework.