Kiyozawa Manshi (清沢 満之?, 1863–1903) was a Japanese Shin Buddhist reformer of samurai background who studied at Tokyo University in Western philosophy under the American philosopher Ernest Fenollosa.
Many Shin scholars feel that Kiyozawa's viewpoints are comparable to the religious existentialism of Europe.
Many Higashi Hongan-ji scholars trace their line of thought to Kiyozawa Manshi, including such men as Akegarasu Haya (1877-1954), Kaneko Daiei (1881-1976), Soga Ryōjin (1875-1971) and Maida Shuichi (1906-1967). Some of his essays were translated into English, such as the book December Fan, and have found a Western readership. Kiyozawa was instrumental to the establishment of Shinshū University in Tokyo in 1901. The university is now known as Ōtani University, and is located in Kyoto near Higashi Hongan-ji. Kiyozawa served as the first dean of the university.
In his life, however, Kiyozawa was an ambivalent figure. He was emblematic of both the need for modernization, and its pitfalls. He was not popular with the members of his temple, who considered his Dharma messages too difficult to understand. Accordingly, many of his disciples were branded heretics. Kiyozawa himself died of tuberculosis quite young and therefore some consider his thought to be immature and incomplete. Even today, many conservative Shin thinkers see Kiyozawa as being emblematic of what had gone wrong with the Ōtani school.