The stranded dog, a 70-pound Rottweiler, was reported around 2:30 p.m. Sunday at Avalon Canyon, fire officials said.
Firefighters called for a rescue unit, but before it could arrive, the dog fell down the cliff to the beach below.
The dog, who was knocked unconscious by the fall, was placed in a rescue basket and transported to animal control officers waiting at Avalon Drive. It regained consciousness and was taken to an emergency veterinarian hospital for treatment.