The unidentified Huntington Beach man fought with the 5-foot shark for about 10 minutes before hauling the fish onto the sand. He used pliers to remove his fishing hook and rolled the shark back into the water.
Witnesses said the shark appeared to be same one spotted by surfers earlier Tuesday morning.
"I was surfing the day the swimmer was attacked by an angry shark after that had been hooked by a pier fisherman and I didn't want to swim with another angry shark," Liz Jason Barber told the Easy Reader News.
Lifeguards cleared the water for a short time after the shark was released.
Manhattan Beach Aquarium co-director Eric Martin said the man who caught the shark was fishing for bat rays and "seemed to know what he was doing."
He described the fish as "a first year animal," and said it wasn't a threat to swimmers.