The incident occurred around 7am on Sunday on the Old Dublin Road.
It was a single vehicle car crash. It is understood the car drove off the road and collided with a fence. The man was pronounced dead at the scene. It is believed that the man is 46 years old from the Rathcoole area. Garda are appealing for witnesses. Witnesses are asked to contact Mayfield Garda Station 021-4558510 or the Garda Confidential Line 1800 666 111.