The crash on state Highway 130 in an unincorporated area about a mile east of Clayton Road was reported around 2 p.m., San Jose Fire Capt. Rob Brown said.
The vehicle had fallen around 150 feet down a ravine, causing major damage and injuring the driver and passenger, Brown said.
One person with minor to moderate injuries was able to get out of the car and was helped up the side of the ravine by rescuers.
The other person, who suffered "significant" injuries, remained trapped in the vehicle for around two and half hours before fire crews were able to free them and bring them up the hill using ropes and pulleys, Brown said.
Both victims were transported to local trauma centers and are likely to survive their injuries, Brown said.
Tow trucks are on the scene now working to bring the vehicle back up to the road, and the road remains closed.