Left ventricular thrombus is a complication of left ventricular dysfunction, including acute myocardial infarction, cardiomyopathy, and severe valvular heart disease. Surgical removal should be considered when a thrombus is mobile, when thromboembolism occurs, and when cardiac function has the potential to improve. Two patients with left ventricular thrombus underwent totally thoracoscopic transatrial thrombectomy. A thrombus developed in the apex of the left ventricle after acute myocardial infarction in one patient (Case 1) and during treatment for congestive heart failure in the other (Case 2). The minimally-invasive transatrial approach requires no sternotomy or left ventriculotomy and is thus particularly beneficial for treating left ventricular dysfunction. Moreover, totally endoscopic surgery confers the advantage of a deep and narrow visual field. Therefore, we consider that this strategy is highly effective for treating left ventricular thrombus.