STARS Air Ambulance was called in to bring the man to hospital in Calgary.
Elk Valley RCMP says the accident occurred on Tuesday, June 4th approximately 15 km north of Elkford on Elk Lakes Forest Service Road.
It was a single vehicle accident that saw the vehicle rollover with two men inside.
"One man who sustained serious injuries was transported to the Foothills Hospital in Calgary by STARS," writes Elk Valley RCMP.
The other occupant suffered minor injuries and has since been released from the Elkford Health Centre.
According to police, the vehicle had no insurance and the vehicle did not have the correct licence plate.
Alcohol is not a factor in the collision.
Elk Valley RCMP are continuing to investigate.