AIM: To valuate the efficacy of 0.01% atropine for controlling myopia in children of different ages.METHOD: A randomized, double-blind, placebo control and single-center study was conducted. A total of 295 myopic children, aged 6～13 years, with myopia of -0.5D～-6.00D and astigmatism ≤2.0D, who admitted to our hospital from May 2019 to May 2020 were randomly assigned to experimental group(197 cases)and control group(98 cases)in a 2:1 ratio. Two groups were further divided into three subgroups according to age, 6～8 years old group(40/26 cases), 9～10 years group(84/34 cases), and 11～13 years group(73/38 cases). 0.01% atropine was administrated in the experimental group and placebo was administrated in the control group once before sleep. The changes of parameters were compared before and at 2wk, 3, 6, 9 and 12mo after treatment. Intraocular pressure, accommodation amplitude, best corrected distance and near visual acuity, pupil diameter and tear film were tested at 2wk. Cycloplegic refraction was assessed before treatment, and at 6 and 12mo after treatment.RESULTS: The spherical equivalent and axial length progression at 12mo after administration was -0.37±0.69D and 0.29±0.24mm in the experimental group, and -0.59±0.65D and 0.37±0.23mm in the control group(P=0.008, 0.006). In 6～8 years group, spherical equivalent and axial length progression between experimental and control group were not statistically significant(t=0.054, P=0.957; t=-0.623, P=0.536). In 9～10 years group, spherical equivalent and axial length progression between groups were statistically significant(t=2.056, P=0.042; t=-2.057 P=0.042). In 11～13 years group, spherical equivalent and axial length progression between groups were statistically significant(t=2.33, P=0.022; t=-2.424, P=0.017). The pupil was slightly dilated and the accommodation amplitude was decreased in experimental group, and the mean pupil diameter of the two groups was 3.94±0.79 and 3.16±0.48 mm respectively at 12mo after treatment(P<0.001). Other parameters and adverse event noted between groups were not statistically significant.CONCLUSIONS: 0.01% atropine is helpful to control the progression of myopia in children, which is well tolerated by adolescents. However, the effect of 0.01% atropine on the control of myopia for children aged 6～8 years is not enough. The findings suggest that increased concentration of atropine can be tried for 6～8 years old.