Fighting World of Japan Pro-Wrestling, known shorthand as World Japan or WJ, is a professional wrestling promotion formed in Japan in 2003.

Riki Choshu , one of New Japan Pro-Wrestling 's top stars who had come out of semi-retirement in 2002 left the New Japan promotion for the second time in the fall of 2002. With Kensuke Sasaki , Shiro Koshinaka , and referee Masao "Tiger" Hattori not renewing their contracts with New Japan in January 2003 as well, the four of them decided to develop their own promotion, World Japan. Yoshiaki Yatsu (who had been Choshu's ally in New Japan, Japan Pro , and All-Japan in the 1980s), was also brought in along with some of the talent of his small-time SPWF promotion. Other independent wrestlers and freelancers such as Genichiro Tenryu , Takao Omori , and Tomohiro Ishii came along as well.

World Japan, however, was viewed by Japanese fans as just another independent promotion in the saturated world of pro wrestling, so it wasn't able to make a dent in the major promotions' fanbases. Despite having tournaments to crown WMG (World Magma Greatest) champions in both the singles heavyweight and tag team divisions, these events didn't draw much interest. Eventually, the major talent (Sasaki, Tenryu, Koshinaka, Omori), went back to the major leagues, while World Japan continued operating on a part-time basis as Riki Choshu's exclusive show. In December 2004, however, Choshu himself appeared again on a New Japan card, indicating that his days of promoting World Japan may be reduced even further or discontinued altogether.