A cardiac injury is one of the most dramatic and demanding emergencies than may be cared by the surgeon. Four patients who sustained penetrating wound of the heart have been experienced in the Depart-ment of Thoracic Surgery, Kyungpook National University Hospital. They were 3 males and one female. The age was between 21 and 25. All of this series had stab wounds on the heart by instruments of scissors, gimlet, kitchen knife and glass. Injured sites were two cases of right ventricle, one of the right atrium and one of indifinitive with pericardial laceration. Three of these patients have been successfully treated by emergency thoracotomy with 3-0 silk sutures for myocardial penetrating wounds. One of these patients occurred cardiac arrest during surgery and expired, who was in penetrated right ventricular injury through which massive bleeded. The classic clinical description of tamponade, Beck`s triad, seemed to be useful for making diagnosis of the tamponade but not entirely reliable as diagnostic criterion of the tamponade. In the studing of 3 tamponade cases in these series, the triad of Beck was presented in only two cases. Elevated venous pressure was thought to be a valuable diagnostic factor in pericardial tamponade.[KTCS 1973;2:189-194]