Authors report two cases of hypothermic patients with Osborne's J wave on electrocardiogram. A 46-year-old male with liver cirrhosis was brought to the emergency room by ambulance due to comatous mental status. On exammination, the body temperature was below 35 ℃. By rewarming using warm normal saline intravenous infusion and hot pack application on the chest, his body temperature rose up to 36 ℃ and regained consciousness. Later, he expired with afterdrop phenomenon. Another 41-year-old stuporous quadriplegic male with post-traumatic cerebral palsy was brought to the emergency room by his family complaining weakness and vomiting. On exammination, the body temperature was below 35℃. He was rewarmed using warm normal saline intravenous infusion and hot pack application on the chest. However, he could not regain his normal body temperature and expired due to irreversible shock.(Korean J Med 59:561-564, 2000)