A case of acute disseminated encephalomyelitis in 13-year-old boy associated with enterovirus is described. The patient had symptoms of severe headache and photophobia for 2 days. Diagnosis was made on the basis of diffuse high intensity white matter lesions in the left frontoparietal region seen on magnetic resonance imaging, and positive enterovirus polymerase chain reaction in cerebrospinal fluid. His symptoms improved substantially without specific therapy, and he recovered without neurologic sequelae.