·AIM:To research the refractive changes in preschool children,to provide information for the prevention and treatment of the ametropia.·METHODS:Totally 466 children aged 3 years old were examined with Suresight hand-held refractometer and followed up for 4 years.·RESULTS:Hypermetropia and the complex hypermetropic astigmatism decreased with the age increase.Emmetropia and spherical myopia increased with the age increase.The axis of astigmatism was quite stable.The spherical diaopter and the cylinder diopter decreased with the age increase.The referent value of all aged groups were gained.·CONCLUSION:It is necessary to investigate the development of refraction in children.Refraction are very important in children’s eye care and the criteria of abnormal refraction in preschool children identified by the age should be paid more attention.·