Surgical treatment for PDA has been pivotal in historical development of surgery for congenital heart disease. A clinical study on 36 cases of operated PDA were performed during period from Aug. 1981 to Jul. 1985 at the Department of Thoracic & Cardiovascular Surgery in Chonbuk University. The following results are obtained. 1. The 8 males and 28 females ranged in age from 2 yrs, to 24 yrs, [mean 11 yrs.] 2. Chief complaints of the patients were dyspnea on exertion in 61%, palpitation in 39%, frequent URI in 12%, and no subjective symptoms in 11%. 3. On auscultation, continuous machinery murmur heard in 94% and systolic in 14%. 4. Radiologic findings of chest P-A showed increased density of pulmonary vascularity in 94%, cardiomegaly in 69%, and within normal limits in 5% of the patients. 5. EKG findings of the patients revealed LVH in 69%, RVH in 6%, BVH in 6%, and within normal limits in 17%. 6. Of the 36 patients, cardiac catheterization was performed in 34 patients. The results showed mean Qp/Qs = 2.25, mean Pp/Ps=0.42, and mean systolic pulmonary arterial pressure=53mmHg. 7. Surgical methods were as followed: The 32 case of ductal ligation and one case of division & suture technique for PDA through the left posterolateral thoracotomy were done. And 2 cases of ductal ligation one suture closure through the pulmonary artery were performed under the cardiopulmonary bypass. 8. Intraoperative complication was ductal rupture with division 8< suture for PDA and transient hoarseness in 1, recanalization in 1, and urethral stricture in 1 case postoperatively. 9. One patient died due to ductal rupture intraoperatively and operative mortality was 2.8%.