Jikōson (璽光尊, 22 April 1903 – 1983/1984), born Naga Ōsawa (大沢 奈賀, Ōsawa Naga) and later known as Nagako Nagaoka (長岡 良子, Nagaoka Nagako), was a Japanese medium, spiritual healer and the leader of a new religion known as "Jiu". She claimed to be the representative of Amaterasu and the ruler of Japan. She was the first of several female leaders of Japanese new religions to attract public attention in the late 1940s.