ObjectiveTo investigate the incidence and relevant factors of visual acuity abnormalities in preschool children undergoing kindergarten entrance physical examinations in Shannan City, Xizang, in 2022, so as to formulate policies for protecting children’s visual acuity and provide a basis for optimizing the children’s health service system in this region. MethodsA cross sectional study was conducted among the children undergoing kindergarten entrance physical examinations in Shannan City in 2022. A diopter examination was performed for these children, and a questionnaire survey was administered to their caregivers. Additionally, factors affecting children’s visual acuity abnormalities were analyzed using the χ² test and binary logistic regression analysis. ResultsA total of 759 children were included in the analysis, with an incidence rate for visual acuity abnormalities of 11.20%. Univariate analysis showed that statistically significant differences were observed in the incidence rate for visual acuity abnormalities among preschool children in terms of different family monthly income (χ²=17.395, P<0.001), father’s education level (χ²=5.133, P=0.023), postnatal vitamin A and D supplementation (χ²=9.575, P=0.008), and feeding method within the first 6 months after birth (χ²=9.330, P=0.009). Multivariate analysis results indicated that family monthly income <5 000 yuan (OR=2.599, P=0.003), insufficient postnatal vitamin A and D supplementation (OR=1.912, P=0.011), and formula feeding (OR=2.131, P=0.010) were relevant factors for abnormal visual development in children. ConclusionThe incidence of visual acuity abnormalities in preschool children in Shannan City is slightly higher than that previously reported in other regions of Xizang. The occurrence of visual acuity abnormalities in children is related to factors such as family monthly income, postnatal vitamin A and D supplementation, and feeding method within the first 6 months after birth. Future interventions should be strengthened on the promotion and dissemination of knowledge related to eye use, such as improve parental awareness of eye care, promote timely vitamin A and D supplementation and encourage breast feeding for children after birth, more specifically, attentions need to be focused on the visual acuity problems of children from low-income families to safeguard the visual health in preschool children in Shannan City, Xizang.