The 42-year-old "Of Men and Mavericks" star was held underwater Sunday afternoon when a set of 15-foot waves rolled in.
The San Mateo County Times says filmmakers were shooting Butler paddling out with competitive surfers Greg Long, Zach Wormhoudt and Peter Mel.
A safety patrolman on a Jet Ski swooped in and picked up Butler.
Wormhouldt says the actor was shaken up but not seriously injured. Butler was taken by ambulance to Stanford Medical Center for examination, and he was later released.
"Of Men and Mavericks" is about Santa Cruz surfer Jay Moriarty, who conquered Mavericks as a teen but died in a free-diving accident in 2001 when he was 23.
Butler's publicist Rupert Fowler didn't immediately respond to an email message sent Tuesday.