A 54-year-old man suddenly felt a strike on his chest while mowing with a machine. At first he had no symptoms except for wound pain, but several hours later, he suffered from high fever with chilliness. The chest roentgenogram showed a foreign body localized within the cardiac shadow. The echocardiogram revealed that the metallic fragment was embedded in the inferior wall of the left ventricle. It appeared that the fragment entered the left ventricular cavity through his anterior chest wall, the right ventricular outflow tract and the ventricular septum. At the operation, the location of the foreign body was again confirmed by the intraoperative echocardiography and the fragment was successfully removed through a left ventricular incision under cardiopulmonary bypass. The postoperative course was uneventful and the case was reported with a review of the literature.