Emergency services were called to the A614 Thorne Road, in the Blaxton area, where a gold Rover 75 is believed to have left the carriageway and collided with a tree at around 10:15am on Thursday, November 15.
The crash happened between the roundabout and Vulcan Way, with the car heading in the direction of Hatfield Woodhouse.A 71-year-old man driving the car was pronounced dead at the scene.
His family have been informed and are being supported by specialist police officers.
It is believed there may have been a delay in the reporting of the crash due to the fact the location is off the carriageway.
Police would like to speak to anyone who saw what happened or anyone who has dashcam footage from the area.
Anyone with information should call South Yorkshire Police on 101 and quote incident number 254 of November 14.