A 45-year old man was admitted to our hospital with chest pain occurring suddenly upon exercise and disappearing with rest within several minutes. A continuous murmur was heard at the upper sternum border. Conventional electrocardiography showed no evidence of myocardial ischemia. Coronary angiography and cardiac catheterization demonstrated a fistula originating from the left coronary artery to the pulmonary artery with an aneurysm 2 cm in size, and Qp/Qs 1.08. Treadmill exercise testing showed no ST-T change at the maximum heart rate of 160 beats/min. Stress/Rest ^99mTechnetium-MIBI single-photon emission computed tomography (SPECT) and ¹²³I-15-(p-iodo-phenyl)-3,R,S-methylpentadecanoic acid (BMIPP) scintigraphy were performed to evaluate myocardial ischemia and ischemia was identified at the perfusion area of the left anterior descending artery. From these results, the patient was diagnosed as having a coronary artery to pulmonary artery fistula with myocardial ischemia. Consequently, surgical treatment was chosen under cardiopulmonary bypass. The determination of a surgical indication using stress/rest ^99mTc-MIBI SPECT and BMIPP scintigraphy is useful in cases showing normal TMT, such as this case.