After being struck by a van travelling at approximately 100 km/hour in Alstonville this morning, a pedestrian is lucky to be alive.

Just before 4am, Friday 25 September, emergency services were called to the Bruxner Highway, near Duck Creek Mountain Road, Alstonville, following reports a man had been struck by a Toyota Hiace van at a speed of approximately 100 km/h.

The pedestrian, a 23-year-old man, was treated at the scene by NSW Ambulance paramedics and the Helicopter Critical Care Medical Team for multiple injuries - including leg, pelvis and head injuries.

The man was placed in a medically induced coma before being airlifted to the Gold Coast University Hospital in a critical condition by Westpac Life Saver Rescue Helicopter.

The driver, a 64-year-old man, was uninjured and taken to hospital for mandatory testing.

Officers from Richmond Police District attended and commenced an investigation into the circumstances surrounding the crash.

The Bruxner Highway is open to traffic but travellers can expect delays.

For the latest traffic information, visit www.livetraffic.com.