Because pupillary dilation caused by muscarinic antagonists is a predisposing factor for glaucoma, we examined the effects of long-term atropine treatment for myopia on intraocular pressure (IOP) and studied the risk factors of elevated IOP among myopic children.A retrospective chart review was conducted in 621 myopic children (aged 6 to 15 years) whose spherical equivalent refractive error ranged from -1.00 to -6.00 D in each eye and who had received atropine therapy. For all children, we collected their complete ocular examination data and IOP measurements beginning in 2008. We then calculated the cumulative dose and the duration of atropine therapy in the 3 years before the date of recruitment to quantitatively assess the effects of atropine therapy on IOP.Four hundred eighty-nine children who received atropine therapy were classified as the "treatment" group, whereas 132 children who did not receive atropine therapy were classified as "reference" group. Statistical analyses did not find any relation between the dose or duration of atropine therapy and the risk of having elevated IOP. However, the age of the myopic children and the spherical equivalent values were positively associated with the risk of having elevated IOP irrespective of whether they had been treated with atropine or not.Topical atropine therapy for up to 3 years seemed to be safe in myopic children; neither the cumulative dose nor the duration of atropine therapy was statistically associated with the risk of having elevated IOP. However, the safety of longer atropine therapy still needs more study. Clinicians should be careful to monitor the changes in IOP among older myopic children or myopic children with more severe myopia.