The purposes of this study were to understand the ideal, actual and the discrepancies between "ideal" and "actual" applications of clinical supervision techniques by intern teachers, mentor teachers, principals, university professors, and investigate the reasons for those discrepancies. In addition to theoretical analysis, the research methods of the study were a questionnaire survey and a semi-structure interview. The subjects of the study were 170 intern teachers, 172 mentor teachers, 46 principals, and 44 professors. The data from questionnaire survey were analyzed using Mean, STD, one way ANDV A, MANDV A, and t-test. Based on the results of the discrepancies between "ideal" and "actual" applications of clinical supervision techniques, four intern teachers, four mentor teachers, two principal, and four professors were identified for a semi-structure interview. The data from semi-structure interview were analyzed with reference to three dimensions for those discrepancies. According to the research findings, this author proposes several suggestions for teacher education institutes, educational administration authorities, and junior high schools respectively.