This Study is objected that an analysis of teacher’s comprehension of their duties and trivial duties which impede their performance as of teacher’s task at school, requirements of the standard of specific technique and performance on teacher’s task and the gap in comprehension of teacher’s task between teachers and administrators. 306 teachers and school administrators in Busan for this study participated in this survey. First of all, most of teachers understand the tasks of Teaching-Learning and Class Management are their duties. On the contrast, they understand most tasks for education attitude and behavior and research and development for their technique and performance and maintain school business are trivial duties. Second, Teachers required specific technique and performance for teaching Teaching-Learning and Class Management in their tasks. They are required less technique and performance for the duties of educating attitude and behavior, research and development and maintain school business. Third, the result of the comparison of comprehension of teacher’s task between teacher and administrators, administrators are hardly recognize in spite of teachers understand many of their task as trivial duties. The same as administrators require teachers to have excessively specific technique and performance for teacher’s task than teacher recognize as analysis shows. Both groups understand the tasks of school discipline and management, counseling students are teacher’s duties. Notwithstanding teachers understand those tasks are trivial duties. Administrator have unlikely recognized the tasks of such as support tuition fee and allowance, various paper works, supervising lunch delivery, sending notice to parents and etc are trivial duties and not required technique or performance. This study shows there are wide gap in comprehension of teacher’s trivial duties between teachers and administrators and Most of teacher’s duties are managed by administrators.