A police spokesman said emergency services attended the single-vehicle crash on a track off Timaru Creek Rd at 6pm.
The vehicle rolled into a ditch, getting stuck on its roof.
The three occupants had to be freed by firefighters from the Lake Hāwea and Wānaka stations, a Fire and Emergency New Zealand spokesman said.
Two people received critical injuries and one was seriously hurt.
A Hato Hone St John spokesman said all three were taken to Dunedin Hospital, two by helicopter and one by ambulance.