The authors describe an anaplastic oligodendroglioma of the cerebellum which is distinctly uncommon. The patient presented with sudden onset of decreased consciousness associated with hemorrhage in the cerebellum, which appeared to origin from a vascular malformation or a tumor on a initial computed tomography (CT) scan. Subsequent magnetic resonance (MR) imaging suggested a high grade glioma with abundant vascularity in the right cerebellum. The histological examination revealed the findings compatible with those of an anaplastic oligodendroglioma. A complicated clinical course had led him to a poor outcome.