Cerebellar glioblastoma multiforme (CGM) accounts for less than 1% of all intracranial glioblastomas; it spreads quickly locally, above all towards the brain stem and adjacent leptomeninges, and has a poor prognosis. We report the case of a 55 year old patient who presented a continuous feeling of dizziness, instability and sickness, with occasionally vomiting and double vision that had started two months before being admitted to hospital. A physical exploration revealed hypaesthesia of the right side of the face, tactile and algesic hypaesthesia in the left side of the body and nystagmus in the bilateral horizontal gaze. Results of the general physical exploration were normal. A magnetic resonance (MR) brain scan revealed a 3 cm expansive lesion in the middle cerebellar peduncle and right cerebellar hemisphere, which was hypointense in T1 and hyperintense in T2. Administering contrast showed it to be heterogeneous, with irregular annular enhancement, and perilesional edema. Subtotal excision of the lesion was performed and pathological analysis allowed a diagnosis of glioblastoma multiforme to be made; radio and chemotherapy were continued. CGM is infrequent and 46.7 years is the mean age of onset. 59% of tumours are located in the hemispheres, they tend to spread locally, and remote metastases have also been reported. Initial clinical manifestations are intracranial hypertension, and gait and balance disorders. Differential diagnosis is provided by MR and includes metastasis, infarction and abscesses. Treatment involves radical surgical excision followed by local radiotherapy. The use of chemotherapy has been reported but its role in the treatment of this entity is still not altogether clear.