Fifteen pediatric (age under 16) cases of oligodendroglioma (ODG) were surgically proven from January 1985 to April 1992 at the Division of Pediatric Neurosurgery, Seoul National University Children's Hospital. To observe the proportion of ODG's in primary intracranial tumors, the location of ODG's and the prognostic significance of the histological grading of ODG's in childhood, the 15 cases of pediatric ODG's were retrospectively analyzed. ODG's accounted for 5.6% of pediatric primary intracranial tumors operated on during the same period. Nine tumors were located in the cerebral hemisphere (3 cases each in the frontal, temporal and parietooccipital lobes), 1 in the thalamus, 2 in the pons-medulla, 2 in the cerebellum and 1 in the thoracolumbar spinal cord. Four tumors were anaplastic and an additional case showed positive cerebrospinal fluid (CSF) cytology for tumor cells. All the cases of anaplasia or positive CSF cytology had a poor outcome. All the seven cases of benign ODG's in cerebral hemispheres presented with seizures which were controlled with or without medication after tumor removal.