Human immunodeficiency virus (HIV)-associated ectatic cerebral vasculitis (HIV-AECV) is a rare form of vasculitis with diffuse fusiform aneurysms. Its pathophysiology remains poorly understood. Although extensively described in children, it is still incompletely studied in adults. Our objective was to present five adult cases with emphasis on imaging findings and long-term evolution. From 2006 to 2014, we included 5 HIV-infected patients presenting with fusiform cerebral aneurysms. Vessels abnormalities were assessed with brain computed tomography (CT) angiography, magnetic resonance angiography (MRA) and/or digital subtraction angiography (DSA). All patients had MR assessment of the brain. Clinical and biological data were analyzed. Fusiform aneurysms of carotid terminations extending to middle and anterior cerebral arteries were bilateral in three patients and unilateral in one. More distal fusiform aneurysms were observed in four patients and saccular aneurysms in two patients, two patients suffered from ischemic lesions while none experienced hemorrhage. Unlike recent reviews, our study underlines the low hemorrhagic potential of HIV-AECV and long-term follow-up suggests a monophasic evolution under antiretroviral medication.