Emergency services were called to Highcliff Rd following reports of a two-car crash shortly after 4.30pm.
Senior Sergeant Craig Brown said a northbound Mitsubishi sedan with three female occupants was involved in a collision with a Toyota Surf with two male occupants on a moderate left-hand bend.
The 20-year-old woman, believed to be the rear-seat passenger of the sedan, was transported to hospital by the Otago Regional Rescue Helicopter.
The woman remained in intensive care in a serious but stable condition last night, a Dunedin Hospital spokeswoman said.
The 19-year-old driver of the vehicle, and a 20-year-old front-seat passenger were taken by St John ambulance to hospital, where they were treated for minor injuries.
The two male occupants of the Toyota Surf were not hurt in the accident. Snr Sgt Brown said alcohol was not a contributing factor.
It had yet to be determined if the victim was wearing a seatbelt at the time of the accident.
A serious crash investigator from Invercargill attended the scene.
The cause of the accident had yet to be determined.
