In order to cope with the demands of the rapidly changing society, advanced countries enrolled in OECD have been establishing corresponding directions as integrating their fields in economy, society, and education as one system. To be a part of the international changes, Korea has presented "Mixed-Use of schools and community facilities." "Mixed-Use of schools and community facilities" enables schools to expand necessary facilities, which were not secured due to insufficient budget, through community funding. Communities could not secure enough convenient facilities because they did not have enough sites for the facilities; however, school sites have made the communities possible to have facilities. As a result, the demand for "Mixed-Use of schools and community facilities" has increased. Therefore, this study redefines the concept of the Mixed-Use of School Facilities in the perspective of the main users, researches the current state of the Mixed-Use of School Facilities through case studies in Korea, and intends to research preferences of the synthesis through surveys. In addition, the study proposes the proper size and the standard of the facilities that are possible to synthesize them with schools. In the future, in running this Mixed-Use of School Facilities business, the data from this study can be utilized.