An optimal pulmonary artery banding is often difficult with a conventional banding technique. It often requires readjustment after closing the chest. So we developed a percutaneously controllable pulmonary artery banding device and applied it in three patients. This device consists of silicone balloon being pasted on a reinforced silastic plate and silicone reservoir. The balloon is applied around the pulmonary artery and the reservoir is implanted subcutaneously. The control of the banding is accomplished percutaneously through the reservoir using a needle with fluid-filled syringe. This device worked successfully in two patients for percutaneous readjustment of pulmonary constriction and congestive heart failure was decreased. This device may offer proper constriction of the pulmonary artery without any surgical procedures after banding and may reduce surgical morbidity and mortality of sick children.