A 20-year-old Tauranga woman with a head injury was flown to Waikato Hospital after a two car crash on State Highway 3, near Piopio.

One other person was flown to hospital by the Waikato Westpac Rescue Helicopter.

The helicopter was dispatched to the scene of the accident, south of Piopio, about midday today.

The woman was treated at the scene by St John paramedics before being airlifted to Waikato Hospital with a head injury.