Abstract: Objective To explore the correlation between injury and school and peer factors among adolescents, and to provide the scientific evidence for the intervention on injury prevention. Methods 4 408 students in grades 7 to 12 were selected through multi-stage stratified sampling in Beijing and Zhongshan city, Guangdong Province. A self-report anonymous questionnaire involving injury, school and peer factors were completed by students themselves. SPSS 20.0 was adopted for statistical analysis. Results 4 309 valid questionnaires were collected. The total incidence of injuries was 15.5% while the incidence of repeated injuries was 4.3%. The incidence of boys (17.8%) was higher than that of girls (13.4%). The incidence in junior high school (17.4%) was higher than that in senior high school (13.6%). The incidence in Zhongshan city (17.9%) was higher than that in Beijing (13.0%). Peer relationship was associated with injury among adolescents. School climate, peer's attitude to risk behavior, friends' delinquent behavior were correlated with both initial injury and repeated injury. Conclusions Injury prevention should base on the characteristics of the injuries among adolescent. School should be considered as the primary place for injury prevention. A supportive environment was beneficial to injury reduction.