Choken (1126 - September 19, 1203) was a Buddhist priest of the Tendai sect who lived from the late Heian period to the beginning of the Kamakura period. His father was FUJIWARA no Michinori (Shinzei). He also used the pseudonyms "Rengyobo" and "Agui no Hoin." Hachijoin Takakura, a Japanese poet on Imperial commission, was his daughter.
Choken studied the Tendai doctrine under Chinken. Initially he lived in Chikurin-in at Kitadani on Mt. Hiei, and later he lived in Agui a satobo (priest lodge in village) of the Chikurin-in. He was exiled to Shimotsuke Province after the Heiji War occurred in 1159, but not long afterward he returned to Kyoto. In 1174, he was appointed as the Gon dai sozu (the provisional second-highest position, upper grade, of priest) due to his learning of the kiuho (service to pray for rain) at the Saishoko (the annual five days of lectures on the Konkomyo-saishoo Sutra); and in 1177 he inherited, from Myoun, the Kechimyaku (lineage) of isshin sangan (threefold contemplation in a single mind). He conducted many hoe (Buddhist masses) as the doshi (officiating monk), and it is said that he was an expert at preaching and instruction in Buddhism and was the originator of the Agui school sermon.
According to "Gyokuyo" (the diary of FUJIWARA no Kanezane), Choken committed adultery with Imperial Princess Shushi, who was the Chugu (empress) of Emperor Nijo, and Kaie, the apprentice of Choken, was a son between Choken and Imperial Princess Shushi.