|The purpose of this study was to clarify the establishment, the background and an educational-system characteristic of Datsans as the educational institution of the traditional Mongolian Buddhist temples in 17~19C. Datsans in Mongol were a specialized educational institution in Mongol at that time, which were in charge of producing Buddhist monks, of researching into philosophy, medicine, astrology, mathematics, literature, and art through the specialized education. This study examined the background of establishing the Mongolian Datsans and described Mongolian traditional philosophy books, which had been written by Mongol’s Buddhist monks in order to systematize Datsans’ education, by classifying them into reference book, teaching material, and guidebook. Also, it figured out the specialized-learning system in Datsans, which was continued for more than about 20 years from the ages of 5~8, the background of its origin in scholar monks, and the examination & title award system. The significance of this study aims to be put in a point of having attempted the introduction of the books with a historical fact on the Mongolian traditional education, which had not been introduced to the country. A work of examining the educational system of Datsans, which had been the traditional educational institutions in Mongol, can be found its value in being able to consider the function that the Mongolian Buddhist temples had possessed, and the aspect of Mongol’s traditional education system, as well as the history of Mongol in those days.