BACKGROUND Until recently, middle cerebral artery (MCA) aneurysms were mostly treated by surgery, and endovascular treatment (EVT) was only performed in selected cases. We prospectively evaluated the feasibility and the results of EVT when it is considered as the first therapeutic option for the treatment of MCA aneurysms. METHODS From April 2004 to April 2005, 32 patients with 32 MCA aneurysms were treated in our institution. Of these, 12 patients presented with subarachnoid hemorrhage and 20 were asymptomatic. Seven patients were surgically treated because of a compressive haematoma (n = 4), a failure of EVT (n = 1), or because EVT was judged unfeasible (n = 2). In 25 patients, EVT was performed and required the use of the remodelling technique in 16 cases and a stent alone in two. Clinical and anatomical outcome were assessed with the modified Rankin Scale (mRS) at 1 month and a conventional angiography at 6 months. RESULTS EVT was successfully performed and resulted in an excellent outcome (mRS = 0) in all patients but one, who experienced a thromboembolic complication and maintained a slight lack of vocabulary (mRS = 1). Immediate anatomical results included 15 complete occlusions, 8 neck remnants, and 2 incomplete occlusions in two patients treated by stenting alone. Control angiographies were obtained in 23 patients and showed 17 unchanged occlusions, five slight recanalisations, and one recanalisation that required a retreatment. CONCLUSIONS This study showed that EVT of MCA aneurysms is feasible with good results in most patients thanks to new endovascular techniques. However, long-term imaging follow-up is mandatory to confirm these preliminary findings, mostly in terms of anatomical stability.