Nikko, Japanese priest, founder of Nichiren Shoshu Buddhism (b. 1246)
Nikkō Shōnin (日興上人, 8 March 1246 – 7 February 1333), Buddhist name Hawaki-bō Byakuren Ajari Nikkō (伯耆房白蓮阿闍梨日興), was one of the six senior disciples of Nichiren and was the former Chief Priest of Kuon-ji temple in Mount Minobu, Japan. Various Nichiren sects in Japan claim to have been founded by Nikkō, the most prominent being Nichiren Shōshū and some lineages within Nichiren Shū.

Nikkō kept meticulous records and highly organized religious practice during his lifetime, and is responsible for much of the records that survive today. Nikkō singularly upheld the doctrine that Nichiren was the True and Eternal Buddha in the Third Age of Buddhism and therefore is considered by schools stemming from Nikkō such Nichiren Shōshū and the Soka Gakkai as the legitimate successor to the ministry and legacy of Nichiren. Nikko established the Head Temple Taisekiji at Fujinomiya in 1290, as well as enshrining the Dai Gohonzon image. In 1332, four months before his death, he designated Nichimoku Shonin as his successor. The grave of Nikkō remains today in Kitayama Honmonji, Omosu, in Suruga Province where he lived for thirty-six years, establishing a Buddhist seminary that affiliated in the Hokke shū (法華宗) religion. The Koshi-E memorial feast of his death anniversary is commemorated on February 6 (Nichiren Shoshu O-tai-ya) and February 7 (Gosho-to-e ceremony).