Right coronary artery to left ventricle fistula is a rare type of coronary artery fistula among congenital coronary artery anomalies. Most patients exhibit no symptoms and some experience chest pain. Coronary angiography sometimes detects the presence of coronary artery fistula, but not coronary arteriosclerosis. A 76-year-old man with unstable angina was admitted because he did not respond to drug therapy. Coronary angiography showed three-vessel coronary artery disease and the contrast agent entered the left ventricle from the terminal of the right coronary artery during diastole. Multidetector-row computer tomography showed similar findings. The patient subsequently underwent coronary artery bypass grafting and obliteration of the coronary artery fistula. The chest pain was relieved and he is now in good condition.