The incident happened on the Holywood Road, Newtownards at approximately 3.30pm on Wednesday.
Three vehicles were involved in the collision according to the Police Service of Northern Ireland (PSNI).
The road had been closed for examination but as since reopened to traffic.
PSNI are appealing to anyone who may have been in the area and may have witnessed the incident, particularly those with dashcam footage, to contact the Collision Investigation Unit quoting reference number 1095.
One person has sadly died following a collision in Newtownards on Wednesday. pic.twitter.com/lfc4QlXyjo
— Police Service NI (@PoliceServiceNI) October 15, 2020
