Early career Ok started his professional MMA career in 2014 and mainly fought in East Asia, particularly
Wu Lin Feng. He amassed a record of 13–3 prior to being signed by ONE Championship.
ONE Championship Ok faced
Marat Gafurov at
ONE on TNT 3 on April 21, 2021. He won the bout by unanimous decision. Ok faced
Eddie Alvarez at
ONE on TNT 4 on April 28, 2021. He won a close bout via unanimous decision.
ONE Lightweight Champion Ok faced defending ONE Lightweight World Champion
Christian Lee at
ONE Championship: Revolution on September 24, 2021. He won the fight by a unanimous decision to win the title. Due to the controversial nature of the decision, it was reviewed by the ONE Competition Committee which ultimately upheld the result. Ok faced Lee in a rematch on August 26, 2022, at
ONE 160. He lost the bout after being dropped by Lee in the second round and being finished on the ground with knees. Ok faced Lowen Tynanes at
ONE Fight Night 10 on May 5, 2023. He won the bout via unanimous decision. Ok faced Alibeg Rasulov for the interim
ONE Lightweight World Championship on July 6, 2024, at
ONE Fight Night 23. He lost the bout by unanimous decision. ==Championships and accomplishments==