Pulmonary stenosis (PS) can be seen from the right ventricular outflow tract to the peripheral pulmonary arteries. Most frequently, the obstruction occurs at the level of the pulmonary valve; however, it occurs less frequently at the infindibular level within the trabecular component of the right ventricle or within the pulmonary arterial pathways. Lesions at any of these levels can occur as part of more congenital cardiac malformations such as tetralogy of Fallot, complete transposition of great arteries, or atrial septal defect. Isolated supravalvular pulmonary stenosis (iSPS) is less common than other types of PS. In this study, we present our experience with 4 patients who underwent cardiopulmonary bypass operation for iSPS. In one patient, the circular stenotic area was noted on the touch point of the pulmonary valve. Right ventricular pressures ranged from 70 to 90 mmHg, and the pulmonary artery mean pressures ranged from 14 to 17 mmHg. In all patients, the left ventricular and aortic systolic, diastolic, and mean pressures were moderately increased. Pulmonary artery stenosis was treated successfully using a pericardial or Dacron patch on cardiopulmonary bypass. Various techniques such as balloon dilation have been proposed to deal with this problem, but these may often be unsuccessful because of the elasticity and recoil of the pulmonary artery constrictive ring. Even though endovascular stenting and/or balloon angioplasty have been recently proposed as an initial treatment strategy, they may be associated with some severe complications including pulmonary artery thrombosis or stent migration. Our study, even though it consists of a limited number of cases, suggests that open heart surgery using an oval-shaped patch may be a used as the other main choice for the treatment of iSPS.