The 24-foot Chaparral caught fire at about 4 p.m. on the weed-filled lake in northern Leon County, according to the Florida Fish and Wildlife Conservation Commission.
Adam Shannon, the 26-year-old boat operator, and passengers John Shannon, Michael Johnson, Allison Johnson and Erin Clenney got in the water and began swimming for shore.
A cell-phone video shows black smoke billowing over the lake shortly after the rescue. Another boater picked up the swimmers and took them to Bull Headley boat ramp. No injuries were reported.