student and their guardian(s). A database was constructed using the EpiData 3.1 (http://www.epidata.dk/). Data were double-entered to reduce errors. Analysis was performed using the statistical software package SPSS v18.0 (SPSS Inc., Chicago, IL, USA). P-value < 0.05 and 95% CI of OR not contains 1 were considered statistically significant.In the final, we surveyed 2217 children and retrieved 2127 eligible questionnaires (effective response rate 96.11%). Of all the respondents, 53.1% (1130/2127) were boys and 46.9% (997/2127) were girls; 56.4% (1200/2127) were left-behind children (whose parents were away in cities, while their children were left behind to be cared for by a single parent or other family members) [7] and 43.6% (927/2127) were nonleft-behind children. The annual incidence of sports injury was 26.52% among school-aged children in rural Zunyi. The main sport when injury happened was running (39.5%), followed by playing soccer (20.9%) and basketball (20.0%). The leading injured body parts were knees (35.1%), followed by ankles (24.5%) and wrists (22.3%). The types of children's sports injuries were mainly skin abrasions (41.1%), followed by sprains (37.1%), fractures (11.5%), and other types of injuries (10.1%). Additionally, most time of the injury was in the afternoon (41.8%) and the most frequent place was at school (43.8%).According to the characteristics of the possible influencing factors, we divided the factors into sustained factors (such as gender, personality, age, left-behind or not, family income, KAP score) which were difficult or even cannot be changed; and instant factors (such as warm-up, BRIEF REPORT