This study aims to investigate how the format of the basic curriculum of social studies has changed for 40 years, from 1974 establishment to 2015 revision, and to determine the change process by extracting the main elements. To analysis the change of social studies in the basic curriculum, we analysed the curriculum documents from 1974 elementary school curriculum for the mentally retarded to 2015 revised special education curriculum. In terms of format, social studies in the basic curriculum has been revised in the way of seeking systemicity and consistency. The process of change in main elements is as follows. First, the basic curriculum of social studies is inconsistent in terms of the scope and the level of contents. Second, the basic curriculum of social studies is reflecting social changes. Third, the basic curriculum of social studies has consistently contained the contents about independent living of the students with disabilities. This is a distinctiveness of the basic curriculum of social studies.