Crash investigators believed fatigue was a factor in this morning's fatal accident near Cessnock.
A Toyota Corolla slammed into a tree on Congewai Road, Congewai just after 1am.
A male passenger in his 20's died at the scene.
Police say he wasn't wearing a seatbelt at the time.
The 28 year old female driver and a 25 year old female passenger escaped with minor injuries and were taken to John Hunter Hospital in a stable condition.