Abstract: Objective Based on the data from the Shanghai students' common diseases and health influencing factors monitoring system and the sleep-specific survey, this study was conducted to investigate the correlation between sleep characteristics and myopia progression among younger school-age children at a primary school in Changning District of Shanghai, so as to provide data support for myopia prevention and control in this age group. Methods One primary school was selected from the common diseases and health influencing factors monitoring system for students in Changning District, Shanghai. A total of 230 first-grade students were included in the study. Myopia and refractive parameters were examined, and sleep characteristics were investigated. General demographic characteristics and myopia-related behavior data of the students were also collected. Sleep characteristics were evaluated in terms of sleep duration, sleep efficiency, and sleep quality, with sleep quality assessed using the Chinese version of the Children's Sleep Habits Questionnaire (CSHQ). Multiple linear regression and binary logistic regression models were used to analyze the association between sleep characteristics and myopia progression among the students of this school. Results Regression results revealed that the total CSHQ score of the students at baseline survey was 48.85 ± 7.15. Their sleep efficiency was (94.49 ± 8.48)%, sleep duration was (9.58 ± 0.93) hours, and the proportion of those with insufficient sleep (< 10 hours) was 78.26%. After adjusting for confounders such as socio-demographic and eye-use behaviors, at baseline survey, students' higher daytime sleepiness scores were associated with lower spherical equivalent (SE) (β=-0.18, 95% CI-0.31 to -0.04) and an increased risk of axial length (AL) / corneal radius (CR) ratio >3 (OR=1.52, 95% CI1.00 to 2.29), whereas longer sleep duration and higher sleep efficiency were associated with higher SE (β=0.18, 95% CI0.05 to 0.32; β=0.17, 95% CI0.04 to 0.31), shorter axial length (AL) (β=-0.15, 95% CI-0.27 to -0.03; β=-0.13, 95% CI-0.25 to 0)) and reduced risk of AL /CR>3 (OR=0.70, 95% CI0.51 to 0.96; OR=0.73, 95% CI0.53 to 0.96) . At baseline survey, children's higher propensity for sleep problems (OR=1.70, 95% CI1.04 to 2.78), sleep resistance (OR=2.26, 95% CI1.36 to 3.75), and higher sleep anxiety scores (OR=2.15, 95% CI1.33 to 3.48) were all associated with an increased risk of AL/CR >3 at follow-up (all P<0.05). Furthermore, higher sleep anxiety scores predicted prolonged AL at follow-up (β=0.03, 95% CI0 to 0.05). According to the mixed-effects model, higher daytime sleepiness scores and prolonged sleep duration were independently linked to reduced right-eye SE (β=-0.05, 95% CI-0.10 to 0, P<0.05) and shorter right-eye AL (β=-0.05, 95% CI-0.10 to 0, P<0.05). ConclusionIn this school in Shanghai, there are problems of insufficient and poor-quality sleep among young children. Sleep problems such as sleep resistance, delayed sleep onset, sleep anxiety, and daytime sleepiness among children may accelerate the risk of myopia progression, while longer sleep duration and higher sleep efficiency may serve as protective factors against the occurrence and development of myopia.