AIM:To investigate the prevalence of myopia among primary school students in Xindu district of Chengdu, and analyze the epidemiological characteristics and related influencing factors.

METHODS: By means of stratified cluster random sampling survey, the first to sixth grade students from 4 primary schools in Xindu district of Chengdu were selected for ophthalmology examination and questionnaire survey, and the statistical analysis was carried out with SPSS21.0 software.

RESULTS: There were 3 324 students participated in the survey, 1 124 students with myopia, and the prevalence rate of myopia was 33.81%. The single factor analysis of myopia found that different genders, different ages, different grades, eating fruits and vegetables and drinking milk frequency, parents supervise and remind students to use eye habits frequently, reading and writing light at home, continuous homework and reading time, sleep time, extracurricular activity time, frequency of going outdoors or doing eye exercises during recess, lying reading or reading in a wobbly car. The prevalence of myopia was different among the students with reading and writing posture and their parents with myopia, and the difference was statistically significant. The difference is statistically significant(P<0.05). Multivariate regression analysis showed that grade, sex, parental supervision and warning eye habits, light of reading and writing at home, continuous homework and reading time, extracurricular time, lying reading or reading in a wobbly car, Whether the posture of reading and writing is correct or not, the condition of myopia of parents is the independent factor of myopia, among them, parents' supervision and reminding of eye habit are protective factors of myopia, and the other indexes are risk factors.

CONCLUSION: Juvenile myopia is related to many factors such as environment, heredity and so on. It is necessary to take appropriate measures as soon as possible to prevent its occurrence and development.