Masamori Tokuyama

Because of his affiliation with North Korea and his experience traveling to the country, he had been banned from entering South Korea and the United States. However, he changed his nationality to South Korean in February 2007. He studied Korean language at Yonsei University in South Korea in March 2007.

Tokuyama was born in Tokyo, Japan as a third generation Zainichi Korean. He made his professional debut in 1994, and challenged the Japanese Flyweight Title twice in 1997, but was unsuccessful both times. He won the vacant OPBF Super Flyweight Title in 1999, and defended it twice. His first world title match was against South Korean fighter In-Joo Cho in 2000, whom he beat by unanimous decision over 12 rounds, becoming the first North Korean to win a boxing world title. He defended his WBC and lineal super-flyweight titles eight times before suffering a stunning first-round knockout loss to Katsushige Kawashima in 2004. Tokuyama returned after a one-year lay-off to fight Kawashima on July 18, 2005. Tokuyama was knocked down in the last round, but dominated Kawashima for the rest of the fight, regaining his title by unanimous decision. He defended his title on February 27, 2006, beating José Navarro by unanimous decision. He relinquished his title after this fight and announced his intention to retire from boxing, but later announced that he would continue his career if he could fight Hozumi Hasegawa for the WBC bantamweight title. Tokuyama finalized his retirement on March 14, 2007, since Hasegawa declined his challenge for the bantamweight title. Tokuyama cited lack of motivation as the major reason for his retirement.

Tokuyama visited North Korea in 2001, and reportedly made a statement vowing allegiance to the leader of North Korea, Kim Jong-il, thanking the leader for his success as a boxer. In 2002, former Japanese prime minister Junichiro Koizumi made a visit to North Korea, which revealed the kidnappings of several Japanese citizens in the 1970s and 80s by North Korea. News of the kidnappings received huge media coverage in Japan, and Tokuyama's website was spammed relentlessly with abusive messages when it was rumored that Tokuyama commented: "They (the kidnapped Japanese citizens) might actually be living pretty happily in North Korea."

Masamori Tokuyama (徳山 昌守 , Tokuyama Masamori, born Chang-Soo Hong, Korean: 홍창수, Hanja: 洪昌守, on September 17, 1974) is a Japanese-born Korean former professional boxer who competed from 1994 to 2006. He held the WBC super-flyweight title twice between 2000 and 2006.