A man in his 60s, named locally as George Fleming, has died following a collision on the Tannyoky Road in Poyntzpass.
The single vehicle collision was reported to police at around 6.45pm on Wednesday.
The road remained closed until around 4.30am on Thursday morning while police carried out an examination of the scene. It has since fully reopened.
Anyone who witnessed the collision involving a blue Ford Focus is asked to contact police by calling the non-emergency number 101.