In early postwar Taiwan, the ROC government regained the sovereignty of Taiwan. At this time, the economy was in extreme depression and the educational policy struck out a new track. Promoting the whole physical education was far-reaching in postwar Taiwan physical education. Among them, senior high school physical education played the most important role in the development of social physical education. However, the research on early postwar senior high school physical education was few and far between. So it motivated me to do research on this topic. In order to understand former educational policy, early postwar senior high school documents, educational laws and regulations, and PE statutes were gathered. Also, diaries for instruction, class schedules, school journals, commemorative albums, memoirs and newspapers were collected to find out the status quo of PE classes and extracurricular activities in those days. Besides, a detailed study of the educational policy and athletic activities was made in order to get a complete picture of early postwar physical education in senior high school. Concerning the then objects of senior high school physical education, the guidelines were the Three People's Principles. The objects were as follows (1)To build up a strong constitution and grow to vigor. (2)To set up public morals, to promote team spirit, and to develop living and military skill. (3)To form hygienic habit and cultivate an attitude of laying stress on hygiene. There were two PE class periods each week. The contents included gymnastics, dancing, play, ball games, athletics, self-defense, aquatic sports and ice sports. Each day students did morning exercises for fifteen or twenty minutes, and they took part in extracurricular activities for fifty minutes. Besides, there were gymnastic exhibitions, sports competitions, outdoor collective activities and health check-ups. Furthermore, athletic facilities were simple, crude and shabby because of the devastating war. Qualified PE teachers were few and far between.. After school, students took part in track and field sports, player basketball, volleyball, soccer and practiced gymnastics. There were frequent inter-scholastic competitions such as basketball, volleyball, soccer, baseball, track and field sports. More often than not, students made remarkable achievements in competitions. Concerning the development of physical education in senior high school from 1945 to 1949, people kept up Japanese rules and exuberantly. But under the circumstances, that is, educational policy and courses were changed, qualified teachers, were few and athletic facilities were simple and crude, there was difficulty in promoting physical education. In a word, senior high school physical education was greatly influenced by social environment. It played an insignificant part.