A 77-year-old man had severe aortic stenosis and continuous atrial fibrillation. We performed maze procedure without left atrial incision( Dallas lesion set) during aortic valve replacement for this patient. Dallas lesion set alternates the isolation of mitral isthmus by connecting ablation line beneath left coronary cusp and noncoronary cusp commissure of the aortic valve with ablation from epicardial side of the upper left atrium. Isolation of posterior wall of the left atrium is completed by ablation from the hole for venting tube at the right inferior pulmonary vein. We have had six cases of maze surgery with Dallas lesion set during aortic valve replacement. All patients were in sinus rhythm at discharge, and there was no bleeding complication or in-hospital death. This technique may be a safe and convenient alternative to maze procedure in patients with persistent atrial fibrillation who are refractory to pulmonary vein isolation alone.