BACKGROUND An increasing number of elderly patients present with intracranial aneurysms. In addition to female gender, an older age is associated with a higher risk of developing a subarachnoid hemorrhage (SAH), and these patients often fare poorly in terms of long-term outcome. It is often thought that elderly patients would especially benefit from endovascular aneurysm treatment. We assessed the clinical outcomes in elderly patients with ruptured intracranial aneurysms (RIAs) who were treated by endovascular procedures. METHODS We performed a retrospective review of a prospective database of elderly patients treated with coil embolization for RIAs. The clinical outcomes were assessed using the modified Glasgow Outcome Scale. The rates of procedural complications and adverse events were also recorded. RESULTS During a period of 5 years, 162 patients with 183 intracranial aneurysms were treated in our hospital by means of an endovascular approach. Among them, 51 patients (31.5%) with a ruptured aneurysm were aged 70 years or older. These patients aged 70-91 years (mean age, 74 years) were treated by coil embolization for RIAs. Among them, seven had a Hunt and Hess (HH) grade of I or II, 42 had an HH grade of III or IV, and 2 had an HH grade of V. Endovascular treatment resulted in 32 complete occlusions (62.7%), 15 neck remnants (22%), and 4 body fillings (7.9%). Procedural complications occurred in five patients (9.8%). The outcomes were good or excellent in 17 patients (33.3%). Three patients (5.8%) who died had an HH grade of IV or V. Rebleeding occurred during follow-up in one patient (1.9%). CONCLUSIONS Coil embolization of intracranial aneurysms is safe and effective in the elderly. However, the morbidity and mortality rates are higher in patients with high HH grades. This finding suggests that the timing of treatment should be based on the patient's initial clinical status.