Nishinoumi Kajiro I (??? ???, February 19, 1855 – November 30, 1908) was a sumo wrestler from Sendai, Satsuma Province, Japan.
He was the sport's 16th yokozuna, and the first to be officially listed as such on the banzuke ranking sheets, an act which strengthened the prestige of yokozuna as the highest level of achievement in professional sumo.