At around 3.45pm today a car was in collision with a motorcycle on the A3059 at the junction with Newquay Road in the St Columb area.
The young male motorcyclist has sustained a serious life-changing injury and was taken to Treliske Hospital.
At this time the road is closed at Mole Valley Farmers with a closure at St Eval.
Motorists are advised to avoid the area while emergency services manage the scene.
Police say the road will be opened as quickly as possible.