The incident was reported just after 11 a.m. near the Upper Barton's Creek boat ramp off Six Forks Road.
A small fire broke out on the boat and was put out with an onboard fire extinguisher, Northern Wake Fire Department officials said.
Four of seven occupants jumped into the lake and were rescued by fire crews and North Carolina Wildlife Resources Commission officers.
Two adults and a fifth child stayed on the boat and extinguished the fire.
A person on the boat later said the boat was serviced just two days earlier and they are not sure what caused the fire.