Myocardial ischemia occurs when myocardial oxygen availability is inadequate to meet metabolic requirements. The common cause of myocardial ischemia is atherosclerotic epicardial coronary arteries. Isoflurane is a potent small vessel-type coronary vasodilator and has the potential for causing regional myocardial ischemia in patients with coronary disease, but it's still controversial. We experienced a case of transient myocardial ischemia during general anesthesia with isoflurane. The patient was a 51 year- old male who underwent a direct clipping of an anterior communicating artery aneurysm. There was no specific abnormality on preoperative laboratory tests except for mild mitral valve regurgitation on the cardiac echocardiogram. He had once experienced several minutes of sudden severe chest tightness just 3 months before admission, but it had subsided without any specific treatment. One hour after beginning of operation, abnormal EKG changes such as ST-T elevation, QRS widening, VPC, ventricular tachytcardia and ST-T depression appeared and then normalized within 2 minutes with stopping isoflurane and using isosorbide dinitrate. He discharged 12 days later without complications. After discharge, Tread-mill test, SPECT and 2D echocardiogram were performed but there was no any evidence of coronary artery disease.