OBJECTIVE: Routine use of prophylactic antiepileptic drugs (AED) has been debated. We retrospectively evaluated the effects of prophylactic AED on clinical outcomes in patients with a good clinical grade suffering from aneurysmal subarachnoid hemorrhage (aSAH). MATERIALS AND METHODS: Between September 2012 and December 2014, 84 patients who met the following criteria were included: (1) presence of a ruptured aneurysm; (2) Hunt-Hess grade 1, 2, or 3; and (3) without seizure presentation. Patients were divided into two groups; the AED group (n = 44) and the no AED group (n = 40). Clinical data and outcomes were compared between the two groups. RESULTS: Prophylactic AEDs were used more frequently in patients who underwent microsurgery (84.1%) compared to those who underwent endovascular surgery (15.9%, p < 0.001). Regardless of prophylactic AED use, seizure episodes were not observed during the six-month follow-up period. No statistical difference in clinical outcomes at discharge (p = 0.607) and after six months of follow-up (p = 0.178) were between the two groups. After six months, however, favorable outcomes in the no AED group tended to increase and poor outcomes tended to decrease. CONCLUSION: No difference in the clinical outcomes and systemic complications at discharge and after six months of follow-up was observed between the two groups. However, favorable outcomes in the no AED group showed a slight increase after six months. These findings suggest that discontinuation of the current practice of using prophylactic AED might be recommended in patients with a good clinical grade.