This paper introduces one remaining volume from Genjimonogatari-sho (Johasho) owned by the Miyagi Prefectural Library which had never been previously introduced and points out its potential to be an invaluable resource in order to understand the development of the original Johasho annotated by Kennyo. In 1578, Kennyo was given the first edition of Johasho by his master Joha when he went to Oushu; he added notes to this edition, copied it by hand, and proofread it repeatedly. As mentioned in the book’s colophon, the proofreading process that began in late November of 1587 was supposedly part of this work.