For 26 months since August 1991, 10 consecutive patients with congenital left ventricular outflow tract obstruction underwent corrective surgery in Pusan Paik Hospital. Their ages ranged from 2 to 18 years. There were 6 male and 4 female patients. According to stenotic site, obstruction were classified into supravalvular [n = 5], subvalvular [n = 4], valvular stenosis [n = 1]. We have performed patch enlargement of ascending aorta [n = 2], supravalvular membrane resection and patch enlargement of ascending aorta [n = 3], subvalvular membrane resection [n = 2], subvalvular membrane resection and left ventricular myectomy [n = 2] and aortic annuloplasty with Dacron patch and aortic valve replacement [n = 1]. Preoperative mean value of systolic pressure gradient were 85.0 $pm$29.2mmHg[supravalvular], 70.0mmHg[valvular], 72.5 $pm$ 22.5mmHg[subvalvular], and 78.5 $pm$ 24.3mmHg[total]. Postoperative mean value of systolic pressure gradient were 31.0 $pm$ 8.9mmHg[supravalvular], 0mmHg[valvular], 15.0 $pm$ 10.8mmHg[subvalvular], and 21.5 $pm$ 13.9mmHg[total]. Postoperative systolic pressure gradient was decreased significantly[p = 0.001]. Postoperative course and short-term follow up results were good except one case of transient heart failure.