Penetrating cardiac injury tends to generally be repaired without cardiopulmonary bypass in the operating room. We herein report the case of penetrating cardiac injury repaired using percutaneous cardiopulmonary support in an emergency room. A 57-year-old man attempted suicide by stabbing himself in the left anterior chest with a knife. Although the patient suffered cardiopulmonary arrest for 7 min in the ambulance, spontaneous circulation was restored following pericardiotomy through emergency left thoracotomy in the emergency room. To prevent coronary artery injury and control the massive bleeding, percutaneous cardiopulmonary support was instituted without systemic heparinization and the cardiac injury was repaired in the emergency room. The patient was then transferred to another hospital on day 46 for further rehabilitation. Percutaneous cardiopulmonary support might be helpful for treating critical patients in an emergency room, even in the case of trauma patients.