Another two people have died on WA's roads overnight, bringing the State's road toll to 92.

An 18-year-old man walking along Armadale Road in Forrestdale about 9.30pm was hit by a tow truck.

He was taken to Armadale Hospital but died from his injuries.

Another man was killed at Cookernup when he lost control of his vehicle and hit a tree.

Police said the man had been travelling south on the South Western Highway when he veered onto the wrong side of the road, overcorrected and hit a tree by the side of the road.

He died at the scene.

On Friday night, an 18-year-old man was killed in a crash in High Wycombe.

Police said the man was driving a Holden Commodore south along Roe Highway, east of Kalamunda Road, when he lost control of the car, drove through a median strip and rolled, before coming to rest on a verge.

A female passenger in the rear was ejected from the car, landing 100 metres away.

She was not seriously injured.

The driver, from High Wycombe, received fatal head injuries and died at the scene.

Four passengers were taken to hospital with minor injuries.

PERTH