From Aug. 1984 to May 1986, 116 cases of cardiovascular surgery including 85 cases of open heart surgery were performed at Korea Veterans Hospital. There were 108 congenital anomalies and 8 acquired valvular heart diseases. Among 108 congenital malformations 92 operations were done for acyanotic group, and 16 operations for cyanotic group. Thirteen cases of open heart surgery for infants or small children under 10kg of body weight were performed, which occupied 15.3 percent of total open heart surgery done in the same period. Common congenital cardiovascular anomalies were ventricular septal defect [40.7%], patent ductus arteriosus [29.6%], tetralogy of Fallot [12.[%], atrial septal defect [11.1%], and pulmonary stenosis [1.9%] in order of frequency. Valve replacement using lonescu-Shiley or Carpentier-Edwards valve was performed for 8 cases of acquired mitral valve disease, and valve replacement using St. Jude valve was done for a case of patent ductus arteriosus with severe mitral insufficiency. There was no mortality in acyanotic congenital malformations and acquired valve lesions, and 5 cases of mortality in cyanotic congenital malformations. Overall mortality was 4.3 percent for total cases and 5.9 percent for 85 cases of open heart surgery.