The group of inmates was working on Highway 29 and Lawrenceville/Suwanee Road when the fatal accident happened. The inmate who was hit was holding the stop/slow sign alerting drivers to the work that was underway.
Officials said the 22-year-old inmate was serving a sentence at the Gwinnett County prison and had been on a work detail for about five months.
The 44-year-old driver who hit the inmate remained on the scene, according to investigators.
"It doesn't appear that DUI, drugs or speed were factors. It's all still under investigation so additional details will come to light," Cpl. Will Rundles with the Gwinnett County Police Department, said.