People on the pier heard them yelling for help and called police, and Manhattan Beach fire and police officers arrived quickly.
Manhattan Beach fire Capt. Dave Schenbaum jumped in and asked for a flotation device.
Schenbaum said he and the man were battered by six or seven waves breaking at the end of the pier.
"We took a little beating," he said, "I jumped in because he was going to die."
Los Angeles County fire Capt. Mike Patterson jumped in after the second man. Crews used flashlights and truck lights to find the man.
Lifeguards rescued the men, who had been hanging onto the pier's pilings for safety.
Both men, who were not identified, were treated at the scene.
Manhattan Beach police said no charges were filed against the two men because they could not prove they'd jumped off the pier.