Early Wednesday morning Bracebridge OPP responded to a single vehicle collision on Muskoka Road North in Gravenhurst.
Officers report the car struck a tree near Lofty Pines Crescent.
Simcoe.com reports there were three people in the vehicle, a 17 year old from Barrie, and 18 year old from Springwater, and a 17 year old from Oro-Medonte.
The teen from Oro received major injuries and was transported to hospital by air ambulance.
The investigation continues and charges are pending.