PurposeTo conduct a large retrospective study of screening refractive error in young children.MethodsThis retrospective study included children aged from 4 months to 8 years in Daxing District, Beijing, who underwent refractive examinations without cycloplegia. It included a cross‐sectional assessment of refractive error screening for all children, and a longitudinal component for a subgroup with data available for two to five visits.ResultsA total of 14,987 children were included in the cross‐sectional study. In the group <1 year of age, the percentage of children with a spherical equivalent (SE) >+2.00 D or with cylinder <−1.50 D was 15.25% and 33.24%, respectively. These were significantly higher than for the 1‐ to 4‐year‐old group (SE 8.1% higher, cylinder 13.2% higher) (χ2 = 53.57, p < 0.001; χ2 = 790.39, p < 0.001). Furthermore, 34.83% of children in the 0‐year‐old group had amblyopia risk factors (ARFs). In the 4‐year‐old group, boys had a significantly longer axial length (AL) than girls (differences in the right and left eyes were 0.53 and 0.56 mm, respectively; z = 5.48 p < 0.001, z = 5.80, p < 0.001). AL increased with age, while the AL difference between boys and girls remained stable at 4–8 years of age. The percentage of children aged 5–8 years with myopia in 2020–2021 was significantly higher than that in 2018–2019 (H = 12.44, p = 0.006). In the longitudinal study of 4406 children (up to 12‐month follow‐up), annual changes in SE were −0.27, −0.06, 0.19 and 0.13 D between 0 and 3 years, and −0.38, −0.58, −0.70 and −0.75 D between 5 and 8 years.ConclusionsChildren's refractive error varied significantly from ages 4 months to 1 year, with a high proportion having ARFs. Children aged 5–8 years showed a trend towards myopia. The prevalence of myopia in the cross‐sectional analysis in 2020–2021 was greater than in 2018–2019. Screening refraction changed minimally over a 12‐month period for children aged 1–3 years, but became more myopic for children aged 5–8 years.