The trio was heading back to a dock between Port Royal and Royal Harbor around 7:05 p.m. when they noticed smoke coming out of a hatch, according to Naples Fire Rescue.
Flames then spread quickly through the 17-foot boat forcing the three people on board to jump into the water, rescue crews said.
Another boater picked up the group and no injuries were reported.
The Greater Naples Fire Boat, Marco Island Fire Boat, and the Florida Fish and Wildlife Conservation Commission responded to the scene.
No further information was immediately available.