The prevalence of refractive error and ocular disorders among infants and young children with severe behavioral problems and developmental disorders is not well defined, particularly in developing countries. We performed a retrospective review of ophthalmic examinations performed during a National Institutes of Health--funded cohort study of very young children in Peru with behavioral problems and at risk for developmental disorders. Two-hundred twenty-two children between the ages of 0 and 4 years (mean 2.2 ± 0.9 years) were examined and 100 (45.0%) had an abnormal ocular exam. Overall, the prevalence of refractive error was 33.3%, nystagmus was 12.2%, and strabismus was 10.9%. Among children with Down syndrome, refractive error ranged from 46.2% at age 2 to 85.7% at age 4. Refractive error and ocular disorders are highly prevalent even at a young age in children with behavioral problems and developmental disorders. Much of the visual impairment in this population is treatable; early identification and intervention can have a lifelong positive impact on neurodevelopment.