Although 1% atropine effectively slows myopia progression, it is associated with adverse effects, including photophobia, blurred near vision, and poor compliance. We investigated whether lower doses of atropine would control myopia progression. One hundred and eighty-six children, from 6 to 13 years of age, were treated each night with different concentrations of atropine eye drops or a control treatment for up to 2 years. The mean myopic progression in each of the groups was 0.04 +/-0.63 diopter per year (D/Y) in the 0.5% atropine group, 0.45+/-0.55 D/Y in the 0.25% atropine group, and 0.47+/-0.91 D/Y in the 0.1% atropine group. All atropine groups showed significantly less myopic progression than the control group (1.06+/-0.61 D/Y) (p<0.01). Our study also showed that 61% of students in the 0.5% atropine group, 49% in the 0.25% atropine group and 42% in the 0.1% atropine group had no myopic progression. However, 4% of children in the 0.5% atropine group, 17% in the 0.25% atropine group, and 33% in the 0.1% atropine group still had fast myopic progression (>-1.0 D/Y). In contrast, only 8% of the control group showed no myopic progression and 44% had fast myopic progression. These results suggest that all three concentrations of atropine had significant effects on controlling myopia; however, treatment with 0.5% atropine was the most effective.