A 42-year-old male had been assaulted by his family over the two previous days and went into a deep coma. When the emergency technician arrived, the patient was in a state of cardiopulmonary arrest. On arrival, his electrocardiogram showed asystole. His body showed swelling with subcutaneous hemorrhage, suggesting multiple contusional wounds. Serum biochemistry evaluation revealed blood urea nitrogen of 80 mg/dL, creatinine of 5.99 mg/dL, creatine phosphokinase of 10,094 IU/L, and potassium of 11.0 mEq/L. Advanced cardiopulmonary resuscitation failed to obtain a return of spontaneous circulation. Laboratory findings revealed rhabdomyolysis, renal failure, and hyperkalemia. Autopsy did not indicate the direct cause of death to be traumatic organ injuries. Because trauma was not the direct reason of death, we speculated that the patient died of hyperkalemia induced by multiple contusional soft tissue injuries, following rhabdomyolysis, hemolysis, and acute renal failure. The physician should maintain a high index of suspicion for hyperkalemia induced by rhabdomyolysis and acute renal failure, especially in patients presenting with symptoms of multiple soft tissue injuries with massive subcutaneous hemorrhaging.