Andrew Johnson was in the neurological intensive care unit of WakeMed with a severe head injury for more than a day before he was taken off life support, authorities said.
Funeral arrangements are pending.
Johnson was a full-time firefighter with the Raleigh Fire Department and a volunteer with the Archer's Lodge Volunteer Fire Department in Johnston County.
The wreck occurred at about 5:15 p.m. Tuesday on Buffaloe Road in the Archer's Lodge community. Johnson and another firefighter were riding an ATV and collided with a car, authorities said.
Kirby Turner, who works full-time with the Rocky Mount Fire Department in addition to serving in the Archer's Lodge department, was treated at WakeMed and released.
Both men were off duty when the wreck occurred.
The state Highway Patrol is investigating the case.