McLane Black Lake Fire Department crews were called to the boat fire and found it drifting and saw that it required a multiagency response, officials said.
Officials said the man tried to put out the fire but became overwhelmed by the flames. He jumped into the water wearing a flotation device.
An off-duty Olympia firefighter rescued the man who suffered burns to his legs, officials said. He was taken to the dock at the Olympia Golf and Country Club where medics met him and took him to Saint Peter’s Hospital.
Firefighters extinguished the flames on the boat using an Olympia Harbor Patrol boat, officials said.
The cause of the fire is under investigation.