Fifteen cases of ventricular septal defect with aortic insufficiency were diagnosed raiograhically and confirmed after operation at Seoul National University Hospital in recent two and half years since 1979. Cineangiographiesof ascending aorta and left ventricle were done in those cases and revealed some characteristic findings. The results of the analysis are as follow ; 1. Among the 15 cases, 14 cases were male and 1 cases was female. Age distribution was from 7 years to 23 years. 2. Those 15 cases were corresponded to 8% among total 193 cases of ventricular septal defect, to 11 % among total 135 cases of aortic insufficiency and especially to 48% among 48 cases of aortic insufficiency below age of 20 years. 3. After operation, 11 cases were confirmed as fubpulmonary type ventricular septal defect and 4 cases as subcristal type. The size of the ventricular septal defects were ranged between 0.6 and 2.5cm in diameter. 4. Regurigitation of contrast media was noticed in cine ao tograhy of all cases, and the grads of regurgitation were II-III/IV in 13 cases. 5. Various types of herniated aortic cusp through ventricular septal defect were seen. In the cases of subpulmonary ventricular septal defect characteristic saccular aneurysm was found in 7 cases. Asymmetry or mild bulging of aortic sinus was found in the cases of subcristal ventricular septal defect. 6. Infundibular stenosis was found in 3 cases with right ventriculography and those were caused by the herniated saccular aneurysm of aortic cusp. 7. It is essential for the diagnosis of ventricular septal defect with aortic insufficiency to undertake biplane cineangiography of ascending aorta and left ventricle in long axial view and right ventriculography should be done in suspicion of infundibular pulmonary stenosis.