Longkan Shoujian, a dictionary completed by a Liao dynasty monk named Xingjun in 997, is used to aid Buddhists in the study of Buddhist text and scriptures. Because Longkan Shoujian cites from numerous sources including yinyishu (dictionaries of pronunciations and meanings), dictionaries published in previous dynasties, and rhyme dictionaries, one must investigate thoroughly when attempting to decipher the phonological characteristics of Longkan Shoujian and the dynasties in which its corpuses were written. Inspired by scholars such as Chung-wen Kung and Tai-song Chu, this study examined the years in which many of the cited materials were completed to verify the dynasties in which the corpuses of Longkan Shoujian were written. Subsequently, this study explored the phonetic component substitution groups for the 400+ canonical and noncanonical Chinese characters that it had organized and summarized; and analyzed the phonological phenomena within. The study results showed that some of the phonological characteristics were similar to those of Northwestern China in the Five Dynasties period, challenging the results obtained by previous scholars using the fanqie association method (which involves separating a character’s pronunciation into two other characters). By not accepting information preached in Qieyun and the phonological system of common languages in China as the gospel truth, this study discovered the different phonological characteristics observed in Longkan Shoujian.