The man, who is about 35, fell just west of Mount Diablo, the CHP said.
Fire department personnel found him in a remote, hard-to-reach area suffering from back and leg injuries.
A rescue helicopter was requested from the CHP at about 2:10 p.m., Officer Ralph Caggiano said.
The helicopter arrived and delivered rescue equipment to county paramedics at the scene, according to the CHP. The man was packaged in a rescue bag and airlifted to a waiting ground ambulance.
The patient was then transported to John Muir Medical Center.
