Officers arrived at the intersection of Winston Churchill Boulevard and Erin-Garafraxa Townline Road, north of Erin and found a pickup had left the roadway and there were serious injuries.
Emergency services responded and the driver & passenger were taken to a local hospital.
The passenger, a 76-year-old of Erin was pronounced deceased. The driver was treated for minor injuries.
The intersection was closed by the West Region Traffic Incident and Enforcement Team reconstructionists to mid-day.
The Office of the Chief Coroner was notified.
The OPP are asking if anyone has any information on the collision to call 1-888-310-1122 or anonymously to Crime Stoppers.