RCMP said the man was driving a half-ton truck when he collided with a guard rail on a bridge shortly after 9 p.m. The vehicle rolled.
The driver was ejected from the vehicle, police said. A passing motorist stopped and attended to the man, who was lying on the highway.
EMS transported the man to a hospital in Fort Qu’Appelle. From there, he was taken to a Regina hospital by STARS air ambulance for further medical treatment.
The highway was closed for several hours, but is now reopened.
Police are still investigating.