The Florida Highway Patrol said the women were traveling to South Florida Sunday for a Spring Break cruise to the Bahamas.
The driver of the sport utility vehicle swerved to avoid a tire in the road. The vehicle overturned, ejecting one of the students from the back seat.
Twenty-one-year-old Christin Lancaster of Tuscaloosa, Ala., was pronounced dead at the scene.
The driver, 22-year-old Lauren Braddy of Raleigh, North Carolina, died later at Orlando Regional Medical Center.
Mary McGinness, 21, of Lookout Mountain, Ga., was in the front seat and is listed in stable condition at the hospital. Hannah Jones, 21, of Dothan, Ala., was treated and released from Parrish Medical Center in Titusville, Fla., with minor cuts and bruises.
Troopers said Lancaster was the only student not wearing a seat belt. Mims is about 45 miles east of Orlando.