We report a case of a six-year-old girl who underwent the Takeuchi procedure for anomalous origin of the left coronary artery from the pulmonary artery at the age of 4 months. The left ventricular function was severely deteriorated before the initial operation and at 6 years after the procedure showed a remarkable improvement. Mitral regurgitation disappeared during the 6 years. The intrapulmonary tunnel was sufficiently patent to provide adequate blood flow for the anomalous coronary artery. This patient showed supravalvular stenosis due to shrinkage and thickening in the equine pericardium used for reconstruction of the pulmonary artery, and this stenosis was successfully released by autologous pericardial patch angioplasty.