We experienced a case of traumatic cardiac contusion accompanied by the rupture of the pericardium after multiple blunt trauma sustained in a traffic accident. A 26-year-old woman who had suffered from blunt chest and abdominal trauma was admitted to our hospital, being unconscious with multiple severe injuries including pelvic fracture, bilateral hemothorax, and multiple fractures in the extremities. The patient was in a shock status. We performed the transcatheter arterial embolization of the internal iliac arteries to control the bleeding, when aortography showed that the contrast media extravasated toward the left thoracic cavity. Immediately, an operation for blunt chest trauma was performed. Blood was flooding out of the ruptured pericardium because of the contusion of myocardium. The postoperative course was uneventful. Blunt chest trauma is usually accompanied by multisystem injury. Therefore, it is imperative to determine the priority of treatment based on preoperative examination in patients having multiple injuries.