Epidermal nevus syndrome (ENS) is a sporadic neurocutaneous disorder characterized by the combination of epidermal nevi with significant central nervous system, eye, and skeletal abnormalities. Hemimegalencephaly and related brain abnormalities are the dominant neuropathologic abnormalities in ENS. Magnetic resonance imaging features of the case reported here revealed enlargement of both cerebral hemispheres and malformed basal ganglia, with incomplete separation of the caudate nucleus and putamen. In addition, the right cerebellar hemisphere was enlarged, with disorganized folia. None of these findings have been reported previously in this disorder.