Primary brain tumors associated with intracranial aneurysm are rare. A combination of glioblastoma multiforme (GBM) with cerebral aneurysm is even more rare. We present a 67-year-old female, who suffered from progressive weakness of the right limbs and dysphasia for 2 days. She was referred from another hospital with impression of having a brain tumor. The non-enhanced computed tomographic (CT) scan of the brain showed a mass lesion over the left parietal region, and another tiny lesion with relatively high density over the left suprasellar region. After admission, the carotid angiogram revealed a 13 x 12 x 14 mm aneurysm with a base about 8 mm from the anterior wall of the left supraclinoid internal carotid artery (ICA) between the left ophthalmic artery and the left anterior choroid artery. We first clipped the aneurysm by a basal pterion keyhole approach. One week later, the tumor was en bloc removed by a small left parietal craniotomy under the guidance of a navigator. The final diagnosis was confirmed by histopathological examination as GBM. After the surgeries, the patient received palliative radiotherapy with a dose of 4000 cGy. She recovered well with no evidence of recurrence of the tumor one year after the operations. In this report, the careful diagnosis and the possible mechanisms of concurring GBM and cerebral aneurysm, as well as the strategies of surgical treatment involving minimally invasive approaches are discussed.