Objective: The purpose of this study is to assess the factors related to the outcome of 84 patients who underwent surgery for anterior communicating Artery(ACoA) aneurysms. Methods: The authors review 84 patients who were undertaken from January 1998 to May 2004. In the management of ACoA aneurysms, the outcome was based on several factors: Clinical condition, Distribution of hemorrhage, Time between aneurysmal rupture and surgery, Direction and shape of the aneurysm. Results: The incidence rate of the ACoA aneurysm was 35%. Seventy four patients were classified as those having a good recovery, but 5 patients suffered from some morbidity and 5 patients died. The rate of good outcome for the patients with Hunt and Hess grade was as follows 100% in grade I, 95% in grade II, 80% in grade III, IV and V. The rate of good outcome for the patients with Fisher grade was as follows 98% in grade I, II and 81% in grade III, IV. Nineteen of 22 patients who underwent early surgery were rated as good, while twenty six of 30 patients for whom surgery was delayed showed a favorable result. The unfavorable outcomes were also attributed by vasospasm or other medical problems. Conclusion: For further improvement of the overall surgical outcome: First, early surgical intervention is recommended for good grade patients. Second, active management of poor grade patients should be scrutinized with early surgery. Third, it is also important to step up the effort to minimize the risk of medical complications to enhance surgical results on top of the mainstay of prevention efforts for vasospasm and rebleeding.