Nichiyo (1556 - January 1, 1641, Japan) was a Shingon Sect priest in the Edo period.
His secular surname was Onodera, connected to the Mochizuki clan in Bushu (Musashi Province). He shaved his head to become a priest at the age of fifteen and went to Mt. Negoro, Kishu Province to learn to be a priest by pursuing his studies. He went to Mt. Koya to escape from Hideyoshi TOYOTOMI's attacks on Negoro in 1585, and later assumed the position of the chief priest at Saikoin Temple in his homeland, Monma-mura Village, Musashi Province (present-day Miyashiro-machi, Minami Saitama-gun, Saitama Prefecture). After a while he was taught by Senyo Sojo (high-ranking Buddhist priest) at Hase-dera Temple in Nara, and became absorbed in the secrets of the Shingon Sect by Genyu Sojo at Chishakuin Temple. He was favored and valued highly by Ieyasu TOKUGAWA and was appointed as the third noge (master) of Chishakuin Temple by the order of the bakufu (Japanese feudal government headed by a shogun) in December, 1612. After that time, he was deeply trusted by Ieyasu and Hidetada TOKUGAWA and additionally was given a temple estate 300 koku (approximately, 54 cubic meters) as a reward for his prayers for victory in the Siege of Osaka. He was also granted Shoun-zenji Temple, which was built by Hideyoshi TOYOTOMI, and established the foundation of Chizan (School) as Chishakuin in Negoro-ji Temple on Mt. Ihobuttcho. He was appointed as gon no sojo (a high ranking priest, next to a sojo) in August, 1617, retired from the position of noge in the winter of 1631, and passed away in January 1, 1641 at the age of 85.