A 70-year-old woman visited a Korean-style hot dry sauna room. The patient had a medical history of hypertension and hyperlipidemia. During the sauna, the patient slept for 30 minutes. During the sleep, the right medial thigh was covered with a fully wet towel. The patient sustained a second-degree burn on the right medial thigh area with multiple bullas. On physical examination, erythema, heating sensation, and swelling around the bullas were noted. The patient was admitted and received intravenous antibiotics for 7 days. A dressing with Silmazine 1% cream (sulfadiazine) was applied twice a day for prevention of local infection. The patient was discharged on day 14 without complication. In this case, the mechanism of the burn was different. Hot air has much thermal energy but is not conducted to the skin directly. A wet towel will have a relatively higher thermal capacity or heat capacity than a dry or damp towel, and the sodden water might be a medium for the conduction of thermal energy. Owing to the global popularity of sauna bathing, it is important to recognize all sources of sauna-related burns.