Abstract: Objective To study the characteristics of sports injuries among primary and middle school students and to provide related preventive measures. Methods A retrospective survey on injuries during previous one year was conducted among 3 600 primary and middle school students selected by means of stratified cluster sampling in Shenzhen city. Results The incidence of sports injuries was 21.61%.The injury incidence of third grade students(9.62%)was lower than that of other grades.The boys had a higher injury incidence than girls(23.93%vs 18.40%),the only-child higher than the non-only-child(26.43% vs 18.24%),and the children from temporary household higher than the permanent residential children (24.07%vs 18.53%).Running,playing basketball and soccer,and skating/skateboard were the main sports causing injuries.The students reported 1 536 absenses of class,4 994 days of activity limitation,and 66 460 RMB yuan of medical expenses due to the injuries.Classification tree analysis showed that playing was the most important risk factor and the boys who liked playing and imitation or mischief were at a higher risk of injury. Conclusion The rate of sport injuries among school children in Shenzhen city is high.Safe management and education should be strengthened in order to prevent injuries among the school children.