The effect of partial resection of the gyrus rectus during the unilateral pterional approach on surgical outcome was evaluated in 194 consecutive patients with ruptured anterior communicating artery aneurysms. Resection was performed more frequently in cases with poor clinical grade, in the acute stage, with superiorly directed aneurysms, and with high-positioned aneurysms. The surgical results were graded into three stages, and the follow-up results into five stages using the Glasgow Outcome Scale. Outcomes for 52 patients receiving gyrus rectus resection were compared with those for 142 patients without resection. There were no apparent effects caused by gyrus rectus resection on outcome.