In a 25-year-old woman, suddenly complaining of irritation and soon after of paretic symptoms in the right upper limb, a CT scan showed a large cystic mass in the left parietal lobe. As cerebral angiography was not helpful, a cystic astrocytoma was suspected. After total surgical removal of the cyst, the histological examination revealed, to our surprise, a syncytial meningioma. The rate cases of similar cystic meningioma reported in the literature are reviewed and the usefulness of biopsy on every suspected cerebral neoplasm is stressed.