The medical literature reports an association between cerebral neoplasms and aneurysm formation. Some related aneurysms are detected during preoperative screening, whereas others are detected during or after surgery. We report a patient with de novo cerebral feeding artery aneurysm that we managed during glioblastoma surgery. We present a brief review of the literature on the coexistence of brain tumors, particularly that related to high-grade glioma and aneurysms. The literature discusses several mechanisms underlying tumor formation accompanied by aneurysm formation. Some classifications were also proposed for grouping such aneurysms. We question the necessity of the routine use of vascular imaging for patients with glioblastoma.