A 9-day-old female presented with a large infra- and supratentorial medulloblastoma was treated by surgery, irradiation and chemotherapy. The infant suffered from vomit a few days after birth. She was hospitalized shortly thereafter, when head enlargement was noted. A CT scan taken on admission disclosed a large mass lesion in the cerebellum, extending to the pineal portion, and marked hydrocephalus. At the age of 14 days, the patient underwent ventriculoperitoneal shunting. When she was 67 days old, the tumor was radically resected. The histopathological diagnosis was medulloblastoma. Post operatively, she was irradiated with 30 Gy to the whole brain and 20 Gy to the tumor site. As chemotherapy, ACNU, 1-(4-amino-2-methyl-5-pyrimidinyl-3-(2-chloroethyl)-3-nitrosourea 1 mg/kg was administered twice per 6 weeks. On discharge at 7 months, her only neurological deficit was nystagmus. One week later, she could not move her legs and was readmitted. A CT scan showed no intracranial changes, but the spinal cord was swollen at Th12-L5 level. Myelography demonstrated a filling defect at the L3-5 level. Following irradiation of the spinal cord, the paraparesis gradually improved. However, her general status was deteriorating and a follow up CT scan revealed recurrence of the intracranial tumor. The patient died at the age of 9.3 months which is longer survival time than previous reported one. Neonatal brain tumors are rare, and there have been only 24 cases of neonatal medulloblastoma. The prognosis for these patients is extremely poor, regardless of treatment. Surgery, radiation and chemotherapy for neonatal medulloblastoma are discussed.