The purpose of setting the file of ocular refractive development is to record the process of eye development in children with plan. Set the individual file and begins at 3 years old till 12. Examination is done every 6 months. Parameters are recorded including power of cycloplegic refraction, visual acuity, keratometer, anterior chamber depth, axial length, intraocular pressure, body height and weight. In this way, can provide very important information as to the prompt intervening in myopia control. It is also the effective and practical way in myopia prevention.