The cause of the accident is currently unknown; however it is understood that the sedan was travelling up the Cunningham Highway, approximately 2-3 kilometres on the Brisbane side of the pass, when the vehicle impacted with the large truck, which was travelling in the opposite direction.
It is believed that emergency services personnel, led by Queensland Fire and Emergency Service officers, extricated the man from the sedan and treated him at the scene.
The Toowoomba-based RACQ LifeFlight Rescue helicopter was tasked to the area at 1.55pm.
The helicopter was able to land at Cunninghams Gap helipad, and the LifeFlight medical team were transported to the scene by Queensland Ambulance Service road ambulance.
The LifeFlight medical team worked with Queensland Ambulance Service paramedics to stabilised the patient, before he was flown to Brisbane Princess Alexandra Hospital in a critical condition with head and limb injuries.
The condition of the semi-trailer driver is unknown.