Ryuki Ueyama (born 17 April 1976 in Tokyo) is a Japanese mixed martial artist who most recently competed in the Lightweight division.
He has fought for organizations such as Fighting Network RINGS, DEEP, Pancrase, Hero's and Pride FC.
Ueyama began his combat sports career with shoot style promotion UWF International under the tutelage of Kiyoshi Tamura.
After his fight with Hasdell, he went unbeaten for over a year and a half with wins over Willie Peeters, Yasuhito Namekawa and Tim Thomas, with draws against Lloyd Berg, Dave Menne and Kosei Kubota.
Ueyama eventually lost on 20 March 2001 against Sokun Koh at Rings - Battle Genesis Vol.
He defeated Seiki Ryo and Takaharu Murahama before beating Eiji Ishikawa in the final to win the tournament.