繼鋼和泰與汪榮寶之後，中國音韻學界注意到漢譯佛典為語音研究材料，並開始不同程度利用這類材料加以考證古音。囿限於材料之不足，迄今我們對遼代漢語音韻面貌所知之甚少。本文擇取遼僧慈賢翻譯的四部佛典，並從中擷取音譯梵咒為材料，先考察慈賢生平、譯經時代，畫下空時間界限，並利用對音還原法，描寫、董理出其譯音規律，進而以此討論漢語聲韻特點及推求漢語音系，並且對此音系所反映之語音層次作出判別，冀能管窺十一世紀有遼一代漢語音系面貌。; The academic circle of Chinese phonology has noted that the Chinese-translated Buddhist canons had become phonological research materials since Alexander von Staël-Holstein and Wang Rong Bao, beginning to verify the ancient sounds with the sort of materials in miscellaneous degrees. Whereas, the visibility of Chinese phonology in the Liao dynasty could be scarcely known because of the limitation of material deficiency. Thus, aiming to draw a time and spatial boundary, this article initially observes the life of the Liao monk CiXian and the era of his translating process via selecting the four Chinese Buddhist canons translated by CiXian and extracting the Chinese transliterations from the Sanskrit mantras as materials. Next in anticipation of scoping the appearance of phonological system of Chinese in the Liao dynasty of the 11th Century, the article would describe, arrange the rules of the transliterated sounds, further discuss the Chinese phonological features and ascertain the phonological system of Chinese by means of transliteration and reconstruction, then distinguish the phonological changes reflected by the system.
