This study, as one of the specific suggestions to satisfy the social needs of life long education and to overcome the limitations of the supply of regional facilities, presents plans for the possibility of the mixed-use of educational facilities and regional facilities as the ultimate objective. By focusing on the space composition of the mixed-use facility to execute the roles of the educational establishment actively and efficiently, the purpose is to present the mixed-use methodology in architectural plan on which functions to combine and by how much, when the mixed-use plan of educational facilities. The investigation objects was the 27 elementary schools in Seoul which have undergone mixed-use of educational facilities work as at August, 2007. And each educational facility was classified mixed-use functions and analyzed for the composition form of functions and the characteristics by functions. And for mixed-use facility, form types were derived from the relationship with the school buildings through the analysis on characteristics, strengths and weaknesses of each types were presented by factor-by-factor plan directions of mixed-use facility.