The woman, who was in her 70s, died at the scene in Ballyholme on Saturday night.
It was reported to police that a Citreon C3 was involved in the incident in Donaghadee Road at around 7.15 pm.
A PSNI spokesman said: “Police attended alongside colleagues from Northern Ireland Ambulance Service, but the woman who was struck by the car died at the scene as a result of her injuries.
“The Donaghadee Road, Ballyholme, has reopened following the incident.
“Police would appeal to anyone who witnessed the incident or who may have dashcam footage available to contact them on 101.”