Ryūshiken Ogawa Tazaemon 柳枝軒小川多左衛門 was a bookstore that was a purveyor of books to the Sōtō school. Ryūshiken published many Sōtō school books, and became a purveyor of books to the Eiheiji 永平寺 in the late Edo period. However, the relationship between Eiheiji and Ryūshiken during the mid-Edo period is still unclear. This paper points out that it is highly likely that the Eihei jōshitsu yawa bosatsukai-gi 永平丈室夜話菩薩戒義 and Hokke-kōshiki 法華講式 copyrighted by Eiheiji were published by Ryūshiken, and examines the relationship between the two. As the result, we learn that Ryūshiken was already a purveyor to Eiheiji in the mid-Edo period, but considering that the copyright had been transferred from Eiheiji to Eihukuan 永福庵 and there were few reissues, it seems that the relationship between the two was still fluid.
