Background: To assess the prevalence and demographics of lower eyelid epiblepharon in Chinese preschool children and to evaluate its association with refractive errors.Methods: In this population-based, cross-sectional study , a total of 3,170 children aged 3 to 6 years from Beijing, China underwent examinations including weight, height, cycloplegic autorefraction and slit-lamp examination of external eyes. The adjusted odds ratios (AORs) and 95% confidence intervals (CI) were calculated to evaluate. The prevalence of lower eyelid epiblepharon in preschool children and its association with refractive errors were analyzed.Results: The prevalence of lower eyelid epiblepharon was 26.2%, which decreased with age with 3-, 4-, 5-, and 6-year-old being 30.6%, 28.0%, 15.0%, and14.3%, respectively. Boys had a higher risk of having epiblepharon than girls with ORs = 1.41 (95%CI, 1.20-1.66) and no significant correlation was detected between BMI and epiblepharon after adjustment of age and sex. Epiblepharon was associated with significantly higher risk of refractive errors including astigmatism (OR = 3.41; 95% CI, (2.68-4.33)), myopia (OR = 3.55; 95%CI, (1.86-6.76)), and hyperopia (OR = 1.53; 95% CI, (1.18-1.99)). Among astigmatic epiblepharon preschoolers, with-the-rule is predominant (80.9%) and epiblepharon severity was associated with astigmatism severity (p = 0.019). Conclusions: There is a high prevalence of lower eyelid epiblepharon in Chinese preschool children, particularly among boys and the youngers. Preschoolers with lower eyelid epiblepharon are subject to higher risk of developing astigmatism, myopia, and hyperopia, than those without. An increased attention should be paid to this eyelid abnormality in preschool population.