The incident happened south of the Tom Lantos Tunnel.
Southbound Highway 1 will be closed "indefinitely" while first responders are on scene, the CHP said.
Crews are working to pull the car off the beach.
It's unclear what caused the car to go over the cliff.
***Major Traffic Collision***— CHP San Francisco (@CHPSanFrancisco) September 15, 2021
SR-1 s/b, just south of Tom Lantos Tunnels will be closed indefinitely for emergency personnel to respond to vehicle over the cliffside. Unknown ETO. Will provide updates here on Twitter. pic.twitter.com/i4boaGxqX7