A patient who developed a left ventricular aneurysm without stenosis of his coronary arteries is presented. A 52-year-old man with a history of severe chest pain 12 years previously, was admitted to our hospital because of right femoral arterial thrombosis. ECG on admission showed QS pattern and ST segment elevation in leads V1-V4. Left ventriculography revealed that the anterior and lateral walls of the left ventricle were akinetic and an aneurysm had developed at the apex. However, the left anterior descending artery was patent without stenosis. Resection of the left ventricular aneurysm and thrombus was performed successfully under cardiopulmonary bypass. The cause of myocardial infarction without a coronary lesion is unknown, but it is assumed that coronary spasm and hypercoagulability may have had some role in the onset of myocardial infarction in this patient.