Ten patients after coronary artery bypass grafting had reoperatinons and eight patients underwent postoperative PTCA at Nihon University Hospital from 1970 to July 1991. The difference of age between the reoperation group and the postoperative PTCA group is not significant. Most patients of the reoperation group and all of the PTCA group were male. Symptoms of the patients who required again surgical treatment or PTCA were almost reattack of angina and many cases were complicated by the coronary risk factors, particularly uncontrolled hypercholesterolemia and smoking. The bypass numbers of the reoperation group in the first operation were 2.1 and those of the PTCA group were 3.5. The difference of them was statistically significant (p<0.05). The period from the primary operation to the second treatment also showed statistically significant difference between two groups (p<0.05) (reoperation group: 81.8 months, PTCA group: 55.7 months). In the reoperation group, there were two operative deaths, two late deaths (not caused by heart disease), and the others remained asymptomatic. In PTCA group, no one had died, but four patients repeated attacks of chest pain after PTCA (mean interval 2.3 months), and two of them underwent re-PTCA. For a symptomatic case whose native coronary arteries or vein grafts show progressive stenosis and who have undergone PTCA, reoperation is recommendable as an effective treatment to relieve the symptom.