To retrospectively evaluate the immediate and long-term clinical results, as well as the angiographic results, of occlusion of middle cerebral artery (MCA) berry aneurysms with coils. This retrospective study had institutional review board approval, and informed consent was obtained. One hundred fifty-four MCA aneurysms in 142 patients were intended to be treated. Complications, patient clinical outcomes, and immediate postprocedural and follow-up angiography results were retrospectively evaluated. One hundred forty-nine (96.8%) of 154 MCA aneurysms (72 ruptured, 77 unruptured) were occluded with coils in 137 patients (99 women and 38 men; age range, 28-76 years; mean, 48 years). Thromboembolic events occurred in 20 (13.4%) and aneurysm perforation occurred in seven (4.7%) of 149 procedures. Endovascular treatment (EVT) was performed without complications for 121 (81.2%) of the treated aneurysms. For ruptured aneurysms, the treatment-related mortality rate was 6% (four of 72 aneurysms) and the treatment-induced permanent morbidity rate was 1% (one aneurysm). For unruptured aneurysms, the treatment-induced mortality rate was 1% (one of 77 aneurysms) and the procedure-related permanent morbidity rate was 3% (two aneurysms). One hundred five (70.5%) of the 149 aneurysms were examined with follow-up angiography at least once. Recurrences were found for 21 (20%) of the 105 aneurysms that were followed up for a cumulative period of 1564 months (mean, 15 months). Of these 21 recurrent aneurysms, 10 increased in size in the interval between follow-up angiography examinations and 11 remained stable. A second treatment was required for 12 aneurysms, and a third treatment was required for one. After repeat EVT, total aneurysm occlusion was attained for nine aneurysms, and a residual neck was seen in two aneurysms. One recurrent aneurysm was surgically clipped. The nine other aneurysms with small recurrences were not candidates for additional treatment. EVT of MCA aneurysms with coils can be successfully performed without inducing neurologic deficits in most patients with ruptured or unruptured aneurysms.