All three crew members escaped the flames unharmed, fire spokesman Brian Fisk said.
Multiple firefighting units, both land and sea, were sent to 1200 Pier J Avenue after they received a call at about 2:20 p.m. that a boat was on fire. When they arrived, rescue boats with water hoses attached to the bow began to douse the flames.
A lifeguard fireboat knocked out most of the flames, which had engulfed the inside of the fishing boat, Fisk said. The fire was fully taken down in about 20 minutes and no other injuries were reported.
It was not immediately clear what caused the fire, but fire investigators were on the scene to determine the cause, Fisk said.