Shuen (771 - July 16, 835) was a Hosso Sect Buddhist monk who lived during the first part of the Heian period. He was born into the Kodani clan. He came from Kitatani in Yamato Province. He is also known as Teisho Zenji.
Shuen studied the Hosso Sect teachings under Kenkei of Kofuku-ji Temple in Yamato Province, served as one of the overseeing monks during the service celebrating the completion of Konpon Chudo Hall on Mt. Hiei in the year 794, and was consecrated by Saicho in the year 805. He became a preceptor in the year 810 and betto of Kofuku-ji Temple in 812, following which he constructed Denpo-in Temple within the precinct of Kofuku-ji Temple where he began conducting Shinmitsue. In the year 827, he was promoted to the rank of Shosozu (junior secondary prelate). He is not the same 'Shuen' who studied the Tendai Sect teachings under Gishin before declaring himself Tendai Zasu (Chief Tendai Sect Abbot) after his master's death in the face of opposition from sect followers, reside at Murosan-ji Temple in Yamato Province, and give rise to so-called 'Muro Tendai' (refer to the works of Hidenori TSUJI). Shuen was also close to Kukai, which indicates that he had an understanding of Tendai Sect and Shingon Sect Buddhism which were both new to Japan at the time.