Police believe a man was hit by a car travelling north on the Nepean Highway, near the intersection with South Road, around 5.50am.

The man is believed to be in his 70s and died at the scene.

The driver of the car stopped and is assisting police.

Police are appealing for witnesses who might have seen the collision. Contact Crime Stoppers on 1800 333 000 or visit www.crimestoppers.com.au

The provisional road toll is 16, compared to 30 at this time last year.