A case of a 73-year-old woman with cerebellar medulloblastoma is described. The patient presented with the classical symptoms and signs of a medulloblastoma, and radiological findings were also consistent with this entity. Nevertheless, because of the patient's advanced age, the possibilities of metastatic tumor involving the cerebellum or a primary cerebellar lymphoma were considered before operation. Pathological examination of the operative specimen showed a classical medulloblastoma with occasional areas of early neuroblastic differentiation. Immunoperoxidase strains for neurofilaments were of help in confirming the neurogenic origin of the neoplastic cells. Although medulloblastomas in adults are not rare, onset after the age of 50 is exceptional, with only two cases on record in patients 65 or older. The present patient seems to be the oldest individual with a cerebellar medulloblastoma thus far reported.