He was Andrew Fisher, 42, of Wallsend, Tyne and Wear.
Mr Fisher was the driver of a white Hyundai which was the only vehicle involved in the collision west of the Dromore roundabout at about 9.05 am on Saturday. He later died in hospital.
His passengers, a woman and three children, were uninjured.
Sergeant Leigh McCulloch, Lockerbie Road Policing Unit, said: “Enquiries are ongoing to establish exactly what happened and we are appealing to anyone who may have witnessed the incident.
“You may have seen the vehicle, a white Hyundai, driving on the A75 previous to the incident and have dash-cam footage that can help us. We ask that you come forward and contact us with any information.”
Anyone with information should contact police via 101, quoting incident number 1262 of October 27.