Georgia State Patrol Public Information Officer Gordy Wright said a northbound tractor-trailer left the left shoulder of Interstate 75 at mile marker 296 just before 2 a.m.
The truck, driven by George Benjamin White, 43, of Hiram, struck a guardrail before hitting a concrete support pillar for an overhead sign structure on the southbound side. The vehicle then rolled onto its side, catching fire.
The sign fell into southbound traffic and was struck by the second tractor-trailer. The driver lost control, causing the vehicle to leave the roadway.
White and a passenger in his vehicle, Jermaine Duriel Smith, 36, of Douglasville, were killed in the crash. The driver of the second truck, Hugh Bruce Duling III, 58, of Powder Springs, was also killed.
The accident closed Interstate 75 for hours in both directions. Northbound lanes reopened just before 5:30 a.m., with southbound lanes opening in stages into Wednesday morning.