A 49-year-old American surfer dude has ditched his board, picked up an AK-47 and joined the fight against ISIS.

Dean Parker, a West Palm Beach, Fla., native, told MailOnline that he “heard God’s call” to join the Kurds in their fight against the jihadists in Syria.

Parker, a granddad with no military experience, was moved by a television report about minority Yazidis trapped by ISIS fighters on Mount Sinjar.

“When ISIS was attacking the Yazidis and they had fled to the mountain, an Iraqi helicopter with a Western journalist went to drop water,” he told MailOnline.

“Women and children rushed in and started piling into the chopper. The cameraman filmed this one mother holding her 10- or 11-year-old son. She was crying, holding him,” he said. “He was looking at the camera and that look of sheer terror in his eyes overwhelmed me with emotions I have never felt before.”

At that moment, he decided to quit hanging 10 as a surf instructor in idyllic Zancudo, Costa Rica, to take up arms against ISIS.

“I knew I had to come, and never in the month before coming here did I have any doubt,” said Parker, who left his family, friends and dog, Gretchen — but only notified them on Facebook on Nov. 2, five days after arriving in the Kurdistan region of Iraq.

Parker, who joined the Lions of Rojava fighters — part of the Kurdish People’s Protection Unit, known as the YPG — wrote that he began his training in Rojava, a Syrian town near the Turkish border.

“The only way to try to explain this, is that I heard God’s call,” he wrote. “The Kurds are the most amazing people, I’m so very blessed. I’m not much for words except I love you all my friends, I’m in very good hands.”

Parker, who attributed his “mental toughness” to his knowledge of martial arts, even said he might stay with the Kurds when the fight is over.

“The Kurds are the most gracious, respectful people I have ever met,” he said. “We are family now. I am so honored to be here.”

ISIS fighters haven’t taken too kindly to foreigners — posting gruesome videos showing the savage murders of US journalists James Foley and Steven Sotloff, US aid worker Peter Kassig and British aid workers David Haines and Alan Henning.

But Parker doesn’t seem fazed and even vowed to return to the waves when ISIS is defeated — this time in the Black Sea.