Gangliogliomas represent only 0.4% of central nervous system neoplasms and 1.3% of brain tumors. They are benign neoplasms with low morbidity and mortality and the patients usually present with seizures, but there has been no adult ganglioglioma with lytic skull lesion. A 49-year-old right handed woman suffering from generalized epileptic seizures was admitted to our hospital. She had also left hemiparesis with 4/5 motor strength. Magnetic resonance imaging and immunohistochemical studies revealed WHO Grade 11 ganglioglioma. Skull X-ray showed the lytic skull lesions. We have to consider gangliogliomas in the differential diagnosis of lytic skull lesions.