@@ Objectives: We sought to investigate the feasibility and safety of totally thoracoscopic repair of a ventricular septal defect.Methods: Totally thoracoscopic repair of a perimembranous ventricular septal defect was performed in 36 pa-tients (16 male patients; age, 5-19 years; average age, 10.2 ?4.5 years). Patients with a pulmonary arterial sys-tolic pressure of 60 mm Hg or greater or with supracristal or muscular ventricular septal defects were excluded. An additional 16 patients undergoing open-chest ventricular septal defect repair were selected as a control group. Through 3 port incisions in the right chest, pericardiotomy, bicaval occlusion, atriotomy, and ventricular septal defect repair were performed by a surgeon by means of thoracoscopy.Results: The cardiopulmonary bypass and aortic crossclamp times were 66.2±21.3 and 36.4±8.2 minutes, respectively. The length of stay in the intensive care unit was 20.0 ?4.1 hours. There were no mortalities and no major complications. Transesophageal echocardiographic analysis 5.2 ?.6 months after the operation showed complete closure of the defect without residual shunt. The intensive care unit (17±2 vs 25±5 hours, P = .01) or postoperative hospital (4.2±1.1 vs 6.7±2.1 days, P = .03) stays in the thoracoscopic group were shorter than in the control group. The percentage of patients who required postoperative opioid analgesics in the thoracoscopic group was lower than in the control group (37.5％ vs 87.5％, P = .001).