The purpose of this study is to examine the nature of upper secondary school system, to develop the criteria that is utilized to analyze school system comprehensively, and to explore the futhre directions of the secondary school system by comparin that of major conturies. In the study three criteria for the school system disgnosis were selected: educational ideal dimension, humen development dimension, and social system relevance dimension. The criteria of each dimension for the study are as follows. The educational ideal dimension comprise three criteria of democratic ideal, universality, humanity, Human developmental dimension comprise three criteria of educational stages, sequence, continuity. The social system relevance dimension comprise two criteria of openness and efficiency, In order to gain some policy directions about upper secondary school system those of major countries such as U.S, France, G.K, Germany, Japan were compared, According to the comparison, these countries have shown the following features. In the structural aspect they are making efforts to intergrate upper secondary schools in which students mihgt select programs to their own interests & aptitues. In the management aspect they are strengthening vocational education as well as general education and offering much opportunities for career deucaion. Based upon the problem diagnosis of Korean ypper secondary school system and the study of school systems in other major sountries the policy directions are as follows. 1)In upper secondary school system schools have more autonomy relating to the goal setting, curriculum, school finance etc. and have accountability for those matters. 2) The upper secondary school system have diverses schools, diverse programs responding to muliple demand from the students and the society. 3) In upper secondary school system students could move more sommthly verically in the aspect of lifelong educaion. Students also could transfer more freely hofizontally among different stream of schools and among schools within same type of schools. 4) In upper secondary school system schools offer the poortunities equally and the quality of educaional provision be maintained equitably irrespective of social class, the wealth of the community and founding institution. 5) In upper secondary school system compulsory educaion be strengthened in terms of the period and contents. 6) In upper secondary school system schools be managed to develop students their mind, emotionm, and physical body more harmoniusly. 7) In upper secondary school system schools be managed to develop students their potential so that school could raise students\' excellence in their achievement. 8) Vocational schools be managed to have dual goals: completion of education and continuation of education. 9) In upper secondary school system schools be managed to raise the continuity and cooperation of different types of schools. 10) Upper secondary schools heve more smooth connection with higher educaional institutions in terms of curriculum and career educaion etc. 11) Upper secondary schools utilize the personnel and resource of the sommunity more actively,and strengthen industry - school relationship, and promote exchange with other schools incfluding schools abroad. 12) Upper secondary schools be managed to raise not only internal efficiency such as school effectiveness, employment of vacationla schools but also social efficiency such as high school graduates\' contribution to the national economy.