They were all traveling in a 2001 Lincoln Navigator heading north on U.S. 19. at about three this morning.
The Florida Highway Patrol says it's uncertain exactly what happened next that caused the driver, 33-year-old Charles Hiers, to travel off the road to the right shoulder.
Troopers say he attempted to gain control, but ultimately the SUV flipped several times.
One of the passengers, 54-year-old Charles Gercak of Crawfordville, Florida, died at the scene.
Three other passengers, including a five-month-old baby, were taken to the hospital.
Troopers say the baby and a 33-year-old woman were not wearing seat belts.