Troopers say the initial investigation shows a person driving a Dodge was headed westbound on Royalton Rd, west of I-71.
Another driver in a Toyota was headed eastbound, when the car went left of center at a high rate of speed to pass traffic.
The Toyota hit the Dodge head-on.
Troopers say the woman driving the Toyota was not wearing a seatbelt.
She was killed in the crash. She has not been identified.
The person driving the Dodge was treated at the scene.