The Kwinana Freeway was closed this morning after two men aged in their 20s were injured in a ute rollover near Greenfields.
The rollover happened about 6:30, on the freeway several metres before the Lakes Road exit in Stake Hill.
Police say the black Toyota Hilux was headed south when it left the road and rolled, which saw the driver and a passenger both injured.
The passenger had to be cut out of the ute by firefighters.
He sustained severe head and leg injuries and was flown to Royal Perth Hospital by the RAC Rescue helicopter.
The driver sustained minor injuries and was also rushed to Royal Perth Hospital by St John Ambulance.
The Kwinana Freeway was closed for several hours as Major Crash investigators gathered evidence.
Drivers headed southbound on the freeway were forced to detour around the crash through the Lakes Road overpass.
Major Crash Investigators are asking anyone who saw the crash, or the Toyota Hilux in the area before the incident, to call Crime Stoppers on 1800 333 000 or report online at www.crimestopperswa.com.au.