Abstract: Objective To investigate the detection of myopia among children and adolescents in Chengdu and to explore the characteristics of eye-using behavior. Methods From September to October 2020, a multi-stage stratified cluster random sampling method was used to select primary and middle school students in Chengdu for a questionnaire survey and visual inspection. The descriptive analysis method was used to analyze the detection of myopia and eye-using behavior, and univariate and multivariate analysis methods were used to analyze the influencing factors of myopia. Results A total of 3 150 primary and middle school students were surveyed in this study, including 1 644 boys （52.19%） and 1 506 girls （47.81%）. The proportion of primary school students was the highest, accounting for 55.62%, and local registered residents accounted for 77.37%. Among them, 1 746 cases of myopia were detected, and the detection rate was 55.43%. Multivariate Logistic regression analysis showed that children and adolescents who often / always read and write with incorrect posture （OR=1.254）, use computers at close range （OR=2.998）, watch TV at close range （OR=2.225）, spend less than 2 hours outdoors every day （OR=2.886）, use eyes in bad environment or posture （OR=3.554）, and use electronic products for more than 2 hours every day （OR=3.102）, were more likely to develop myopia. Conclusion The detection rate of myopia among children and adolescents in Chengdu is relatively high, and the prevention of myopia among children and adolescents in Chengdu still needs to be strengthened. While encouraging them to increase outdoor activities and reduce electronic screens, they should correct incorrect reading and writing postures, intervene with eye-using behavior in close quarters and adverse environments, and form a healthy eye-using behavior habit.

Key words: Children, Adolescent, Myopia, Eye-using behavior characteristics, Influencing factor