K-1 World MAX 2005 Japan Tournament was held in Tokyo at the Ariake Colosseum, on Wednesday, February 23rd, 2005. It was the fourth K-1 Japan MAX tournament (70 kg/152 lb weight class), featuring ten of Japan's best fighters. All matches were fought under K-1 Rules except a "Superfight" between Caol Uno and Serkan Yilmaz which was conducted under K-1 MMA Rules. The main event of the evening was the contest between two previous K-1 MAX world champions - 2002 winner Albert Kraus against 2004 winner Buakaw Por.Pramuk.
