AIM: To analyze ocular parameters and refractive status in children aged 3-12y and to explore differences in these parameters across age groups with identical refractive status for studying refractive progression. METHODS: Demographic characteristics, cycloplegic refraction data, and ocular parameters of the participants were collected. Changes in ocular parameters were described according to different age groups. After adjusting for refractive factors, the relationship between age and ocular parameters was explored. Standard regression coefficients (β) obtained from multiple linear regressions were used to compare the magnitude of the effect of age on the parameters and ocular components on refractive power. RESULTS: Data were collected from the right eyes of 1504 participants. Lens thickness (LT) decreased with age, whereas the axial length (AL) and anterior chamber depth (ACD) increased. In the high-hyperopia group, changes in age were only associated with AL and LT. In the low-myopia group, the increase in age was also associated with corneal astigmatism. In the overall model, the β value for LT was the highest at 0.41, whereas β for ACD and AL was significant in all groups except for the high-hyperopia group. The β value of the LT on refractive power in children was slightly greater in the low age group than in the high age group. CONCLUSION: Among children with the same refractive status, the older the age, the longer the axis length and the thinner the lens. The lens affected refractive power in children in the younger age group more than in the older age group. The ocular parameter most affected by age was LT.