A 27-year-old Aveley man died in the first crash in Gidgegannup when his eastbound Mitsubishi Outlander collided with a Mitsubishi Triton travelling in the opposite direction.
The Outlander left the road and hit a tree, while the Triton ute rolled and also hit a tree about 3.20pm.
The driver of the Outlander was taken to Swan Districts Hospital and died a short time later, while the other driver received minor injuries.
In a separate crash on Toodyay Road in Toodyay, a Hyundai sedan and a Hino truck collided at the intersection of Northam-Toodyay Road.
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READ NOWThe 79-year-old Toodyay man driving the Hyundai was taken to hospital but died a short time later, while his 76-year-old female passenger was taken to Royal Perth Hospital with life-threatening injuries.
Major Crash investigators would like to speak to anyone who saw either of the crashes.
Call Crime Stoppers on 1800 333 000.