A 21-year-old motorcyclist has died on the NSW south coast after colliding with a car on Tuesday morning.

Police believe the man riding a BMW motorcycle crossed onto the wrong side of the road in front of a Toyota sedan on Moss Vale Road, Barrengarry at about 7.20am.

Ambulance officers treated the man at the scene but he later died.

The 56-year-old male driver of the sedan did not suffer injuries.

Police are investigating the incident and will prepare a report for the coroner.