The year he turned 22, he debuted as a pro through TFC in late 2013 and lost a decision to Kim Jae-young in his first fight. He had been a swimmer, joined the Marines in December of his senior year of high school, and took up mixed martial arts after discharge.
The year he turned 25, he beat Grigory Sirenko in Vladivostok, Russia, in November by first-round rear-naked choke without being hit once. In 2017, he beat Ray Cooper in Guam, Jung Se-yoon in Seoul and Koji Shikuwa in Nagoya in a row, by submission or TKO. In July 2018, he beat Glenn Sparv by unanimous decision in the RFC 2 main event in Taiwan, and in December he beat Matvey Ivanenko by first-round punch TKO in Khabarovsk, Russia, to win the Real Fight middleweight title and extend his winning streak to seven.
The breakthrough yearIn April 2019, the year he turned 28, he was confirmed for the UFC as the Russia Real Fight middleweight champion. On Aug. 31, 2019, he made his UFC debut in Shenzhen, China, losing to Anthony Hernandez by second-round submission. He was the 17th South Korean, and the second in the middleweight division, to sign with the UFC. In December, he beat Marc-André Barriault by unanimous decision in Busan for his first UFC win in his second fight.
In 2020, he beat John Phillips by 3-0 decision in Abu Dhabi, United Arab Emirates, for his second straight win. In May 2021, he beat Tafon Nchukwi by decision for his third straight win, but in October he was knocked out by Gregory Rodrigues, ending his bid for a fourth.
In 2022, he beat Eryk Anders by decision and Joseph Holmes by submission for two wins in a row. In 2023, he beat Denis Tiuliulin in February and Albert Duraev in July, both by submission, for four straight UFC wins, tying the Korean record held by Dong Hyun Kim. He did not enter the official rankings, and in December a decision loss to André Muniz ended the streak.
In October 2024, he beat Brad Tavares by decision for his eighth UFC win. In June 2025, he beat Ismail Naurdiev by decision for his ninth UFC win, but in October a decision loss to Ikram Aliskerov cost him a 10th win and a place among the ranked fighters.
In March 2026, he withdrew from a scheduled bout with an injury requiring surgery, and in September he took part with Da Woon Jung as a judge and coach in the development survival project TFC Contenders.
Jun Yong Park (born 1991) turned pro with TFC in late 2013, the year he turned 22, and became known when he made his UFC debut on Aug 31, 2019, the year he turned 28. In 2023, the year he turned 32, he won four straight UFC fights, tying the Korean record.
Ages are by calendar year (the year minus the birth year), birthdays aside.