A prospective multicenter study design was adopted. Children aged 6-9 years with premyopia who met the criteria were screened and administered after completion of baseline assessment. Phase I: 0-24 weeks (0-6M). 0.01% atropine eye drops, once daily, at point in both eyes. Phase II: 24-48 weeks (6-12M). According to the rate of myopia progression at 0-24 weeks (6M), the atropine concentration was increased in steps; once daily, at point in both eyes. Group A: ( SE ≤ 0.25D), continued to maintain 0.01% atropine. Group B: (0.25D \< SE ≤ 0.375D), converted to 0.02% atropine. Group C: ( SE \> 0.375D), converted to 0.04% atropine. Followed up 5 times (0, 3, 6, 9, 12 months), collected refractive, ocular axis, intraocular pressure and other data, and recorded adverse events and cost information synchronously. Statistical analysis was carried out by covariance analysis and multivariate model, and pharmacoeconomic evaluation and drug proportion analysis were carried out.