1,597 cases of operation on the cardiovascular disease were performed at the Hanyang University Hospital from 1972 to 1987. Of these, 1,005 cases were open heart surgery. It was started from July 1975. Among the open heart cases, 725 were congenital heart diseases and 280 were acquired heart diseases. In congenital heart cases, 554 were acyanotic and 171 were cyanotic. The operative results were as follows; the overall mortality of cardiovascular surgery was 7.1%, the open heart mortality was 9.5%. This analyses were reported in memory of the achievement of 1,000 cases of open heart surgery.