A modified Fontan procedure was performed on two patients with Univentricular heart. The first patient had UVH of right ventricular type with trabecular pouch and had various associated anomalies, such as common atrium, common atrioventricular valve and combined pulmonary stenosis. The second patient had UVH of left ventricular type with outlet chamber and the associated anomalies were atrial septal defect, tricuspid stenosis and combined pulmonary stenosis. Postoperative hemodynamic insufficiency, fluid retention and renal insufficiency were occurred in the first patient, but relieved with the aid of inotropics and vasodilators. We thought that the good postoperative course and surgical result were gained from the widely patent atriopulmonary anastomosis.