The aims of this study are to gain adequate treatment and prevention of injury. We have undertaken a study of 115 (185 cases) unselected Hanyang University players (foot ball, base ball, basket ball and Volley ball) from Jan. 1975 to Dec. 1977. The results were as follows: 1. The first grade showes high frequency in injury. 2. The injuries of extremities are more of ten than head and trunk. 3. The order of frequency of injury is as follows; foot ball, base ball, basket ball and volley ball. 4. Contusion is most frequent in foot ball but sprain in oters. 5. The highest incidence of players were forward in foot ball, pitcher in base ball, center in basket ball and st riker in volley ball. 6. Many injuries are developed during jumping and running. 7. Hard training and overwork showes high frequency in cause of injury. 8. The six (5.6%) patients can not return to playing.