Anaplastic mixed gliomas are rare tumors that occur mostly in the cerebral hemispheres. They have a distinctive histological appearance characterized by the presence of two or more glial cellular constituents. The incidence of malignant mixed glioma of the brainstem and posterior fossa is extremely low. The authors report an unusual case of an exophytic malignant mixed glioma. Following subtotal resection, the patient received conventional radiotherapy, but continued to deteriorate, and died five months after surgery. The extensive literature review focuses on histopathology, clinical features, natural history, and possible treatment modalities of this unusual neoplasm.