Ontario Provincial Police said a vehicle was heading south on Sydenham Road in South Frontenac Township at about 3 a.m. Tuesday when the driver lost control.
The vehicle then struck a rock face on the road's west side.
The driver, a man, was the only person in the vehicle and he was pronounced dead at the scene.
Beagle survived crash, stayed by crash wreckage
First responders found the man's dog next to the car, according to OPP Const. Jim Morris. The small beagle was also in the car but it survived.
The dog kept returning to the scene of the crash, Morris said, and laid down next to the car.
Police have closed Sydenham Road in both directions between Railton and Orser roads for the investigation and the road should be closed until late morning.
The cause of the crash has not yet been identified. The victim's name has not been released.
Traffic was being detoured at Railton to the north and Orser to the south via Stagecoach Road.