In recent years, there has been a policy trend to merge and integrate small-sized schools in different school levels to prevent school closure and to increase efficiency of financial management of small sized schools in Korea. However, despite high policy interest, many integrated operation schools still face considerable limitations. The purpose of this study is to analyze the problems and improvement requirements of the integrated operation school through interviewing teachers who are working at the integrated operation schools and regional educational office government officials. First, results from this study show that major challenges faced at integrated operation schools include lack of cooperation between teaching staffs due to disparity in teaching culture and teacher qualification system. Moreover, it was found that teachers show low interest in their counterpart’s curriculum and student learning. Second, class hours were different for each school level, so there were considerable difficulties in curriculum operation, professional learning community operation, school facilities and equipment operation. Third, there is no dedicated support department designated for integrated operation schools in the regional Office of Education, and budget is allocated separately for each school level. In addition, teaching and administrative staffs show low preference towards working in the integrated management schools because concurrent positions are not recognized in current school system, which lead to insufficient incentive. Based on these analysis results, this study proposed revising the guidelines for managing integrated management schools, providing training for teachers assigned to integrated schools, providing multiple qualification training for elementary and secondary school staff, establishing integrative school leadership system(school principal) in order to improve integrate school management.