A desmoplastic infantile ganglioglioma occurred in a 5-month-old boy, manifesting as delayed psychomotor development. Computed tomography showed a large cystic mass involving the left occipitoparietal lobes. The tumor was totally removed. He has survived for 13 years without tumor recurrence. Histological examination disclosed marked desmoplasia intermixed with mature-looking ganglion cells, neoplastic glial cells, and small, immature round cells. These clinical and histological features enabled the diagnosis of desmoplastic infantile ganglioglioma.