Left ventricular aneurysms are seen rarely in primary percutaneous coronary interventional era. True aneurysms are usually localized to apex of the ventricle and it’s very rare to develop in the inferior wall. In this paper, we presented a true left ventricle aneurysm, localized at the basal inferior wall which is developed in the course of subacute inferior myocardial infarction of a 74-years-old man. Aneurysm is detected during left ventriculography. The true ventricular aneurysm and consequent severe mitral regurgitation caused by tethering of mitral aparatus are confirmed with transthoracic echocardiography.