Jiao shi yi lin was popular in the late Han Dynasty and declined gradually in the Sui and Tang Dynasties. During the dynastic change between the Sung and Yuan Dynasties, it was hard to find this book, even in Xinan area, which was reputed as “southeastern Zou and Lu”. The representative yiologist in Xinan area, Hu Yi-gui, insisting in Zhu Xi’s yiology, elucidated Jiao shi yi lin in Zhouyi qi meng yi zhuan; e.g., he pointed that the lintzu (lines of verse) should be classified into the category of poetry, which was a quite prospective opinion at that time. Hu Yi-gui focused on the two methods of Jiao shi yi lin, i.e., bian gua and zhi ri. His commentaries on Jiao Gan’s and Zhu Xi’s bian gua let us know a little about the inclination of the scholars in Xinan area to insist in the Confucian classics-oriented philosophy and respect Zhu Xi’s yiology. On the other hand, the incomplete literatures caused by dynastic change misled Hu Yi-gui, which led to his confusion of Jiao Gan’s “one hexagram governs one day” and Fei Zhi’s “one line governs one day”, which were actually two different zhi ri methods. The mistakes were enumerated and corrected one by one in the current study in order to facilitate the researchers in the future.