By studying the avoidance of feudal taboo on emperors' names in the perusal of 48 extant versions of Yi jin jing (Classic of Changing Tendon), together with their contents, it is found that these versions are of valuable editions and 15 of them can be viewed as the early representative works of Yi jin jing, including 8 hand copied versions, and 7 blockprinted versions. No version of the Ming Dynasty can be found. The earliest versions are all transcribed ones, while the earliest extant blockprinted version appeared until the Daoguang reign of the Qing Dynasty. The preface of Shen's checked version doesn't avoid the emperor's name, saying that it was written in the "xin chou" year of Shunzhi, hence, it should be copied in the early Kangxi reign, and is the earliest hand copied version. The hand copied version of Yongzheng reign avoids the word "xuan", yet doesn't avoid the word "hong", also with a preface written in Yongzheng reign, indicating that this one is the earliest next to the previous one. Since the Xidi version avoids both the words "xuan" and "hong", it should be copied during or after the Qianlong reign. The earliest extant blockprinted edition is the one checked and printed by Fu Jin-quan in the third year of Daoguang which might also be the earliest blockprinted edition. That collection by Zhu Wenlan and Laizhangshi might be all later editions.