Most historians studying Korean culture-history have emphasized the role of Buddhism in light of contribution of traditional architecture or art crafts. The main purpose of the research is to analyze the activities of Gong- Yeok monks(供役曾) who were in charge of such Buddhist services as building construction, artisan work and public engineering works etc. The Gong- Yeok monk showed intensive engineering technology and outstanding crafts method ; accordingly, the government and temple authorities appointed them the craftsman for public works or handicraft for Buddhist service. It was also true that they did crucial role in constructing new Capital for Chosun dynasty. The writer referred to such historical documents regarding the monks as Koryo Sa(高麗史), Koryo Sa Jeol YO(高麗史節要), Chosun Wangjo Sil Rok(朝蘇王朝實錄) and Kyung Guk Dae Jeon(經國大典) ; additionally, consulted with some inscriptions and the personal collection of works(個人文集). In the third chapter, the writer has scrutinized the development and dissolution of the organization in light of government control. In the fourth chapter, the writer has analyzed the monk's activities and organic body for building in relation to government system. In the fifth chapter, the writer has examined the monk's activities with the special reference to the monk craftsman who worked for constructing new Capital, castle walls, and Sung Rai Mun(?禮門). Throughout the study, one may find out the national policy on Buddhism ; furthermore, how the government authorities had recognized on socio-politicallevel of the Monk group. The study on Gong- Yeok monk lead us to the following conclusion. The monk group was organized for the purpose of rendering services for Buddhist services and national engineering works or public works. The organization of Gong- Yeok monk system was stemmed from functional development and technological accumulation since early Koryo dynasty. Subsequently, the policy had handed down from the Koryo to the Chosun dynasty. As a result, one should pay attention to the role of the monk organization as the successor old Korean culture.