The patient was a 69-year-old man who called an ambulance due to dyspnea. When emergency medical technicians found him, he had collapsed into deep coma in front of his house. On arrival, he remained in a deep coma with severe hypoxia. He underwent tracheal intubation. An electrocardiogram showed ST elevation. Chest roentgen showed bilateral butterfly shadow. Cardiac ultrasound revealed diffuse hypokinesis. Head computed tomography (CT) showed early cerebral ischemic signs that had been initially overlooked. Urgent transcutaneous coronary angiography showed obstruction of the right coronary artery that was treated successfully. However, the next day, he was still in coma and demonstrated anisocoria. Repeated head CT showed diffuse cerebral infarction. He died on the 5th day. We herein report a rare case of cardio-cerebral infarction with a fatal outcome. Patients with acute myocardial infarction and a coma state should be evaluated for cerebral perfusion or occlusion of major cerebral vessels by enhanced CT or an aortogram if percutaneous coronary intervention is performed.