The philosophy of naturalism has significant relation to education and J. J. Rousseau is a representative of naturalism. This study was based on his writings, Emile, and it contains J. J. Rousseau’s thought of education and physical education. As a result of this study the following conclusions are summerized: 1. J. J. Rousseau’s thought of education became the basement of the formation of the democracy and the new education in the twentieth century. It also had an direct effect on the thought of education of pestalozzi and Phianthropismus and Dewey’s progressivism. 2. J. J. Rousseau’s thought of physical education divided human developmental stage in to five stage (i. e, Animal stage, Savage stage, Pastoral stage, Social stage, Adult stage) and he placed emphasis on the need of adeguate physical activity according to developmental stage and the value and role of physical education as education. J. J. Rousseau’s objective of physical education is the completion of the health body and tough physical fitness. 3. His view of health had an emphasis on the spontaneous, free physical activity of children and he emphasized that the fresh air and nourishment and the sleep after exercise and fatigue need for health. He also placed emphasis on the need of play and recreation and the fact that the sight clothes to the body is harmful to growth development. 4. His view of body is based on the dualism of body and mind and the body and mind are not constrative subjects but reciprocal ones.