Masamori Tokuyama

Masamori Tokuyama (徳山 昌守, Tokuyama Masamori; born Hong Chang-soo; 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.

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.