Eun (798 - October 31, 869) was a Buddhist monk of Shingon Sect in the early Heian period. His secular family name was Azumi clan. He hailed from Yamashiro Province. He was one of eight priests who went to Tang for study (Saicho, Kukai, Jogyo, Engyo, Ennin, Eun, Enchin and Shuei).
He initially studied the doctrine of Hosso Sect under Taiki of Todai-ji Temple and Chukei of Yakushi-ji Temple, he became in 824 a disciple of Jichie, a monk of Shingon Sect, after receiving religious precept. After he served as a proofreader of hand-written Issai-kyo Sutra in the Kanto region and a lecturer at Chikushi Kanzeon-ji Temple, he went to Tang in 842 on a ship owned by Ri Shojin, a merchant of Tang. He received Kanjo (a ceremony to be the successor) from Gishin of Changan Qinglongsi Temple (Xian City) and thereafter, made a pilgrimage to Mt. Wutai Shan (China) as well as Tendai-san. He returned to Japan in 847 and submitted Hakke Shorai Mokuroku (the catalogue of books brought back from Tang by eight priests). At the wish of a nyogo (a high-ranking lady in the court (a consort of an emperor)), Fujiwara no Junshi, he founded Kyoto Ansho-ji Temple (Kyoto City) in 848. Later, he was conferred the title of Sozu (a title of high-ranking priest) and was called Ansho-ji Sozu.