Ventricular septal defect associated with patent ductus arteriosus is well known cardiac anomaly that can be treated successfully by operation. This anomaly is found at low frequency. Seven cases of the combined malformation were operated on during the period from 1959 to 1978 in the Department of Thoracic Surgery, Seoul National University Hospital. Right heart catheterization and retrograde aortogram can diagnose the disease correctly. Staged operation in one case and one-stage operation in 5 patients were done. In all cases of the open heart surgery the closure of the ductus was done by transpulmonary suture of the PDA opening. Among 6 patients of the open heart surgery 2 operative death [33.3%] and one late death [total 50%] were noted. Four type II and one type I and one Type IV VSDs were found. In one case the anomaly was accompanied with aortic insufficiency by herniation of the right coronary cusp through Type I VSD.[KTCS 1979;3:233-239]