Malignant hyperthermia (MH) is a rare condition that occurs in susceptible patients exposed to triggering anesthetic agents. Clinical signs of MH are increased end-tidal carbon dioxide, tachycardia, arrhythmia, and hyperthermia. As for human medicine, MH is known to be a serious complication of anesthesia in the veterinary field. Although MH requires prompt and proper treatment, clinical reports of MH in veterinary science are limited. We experienced a suspected clinical case of MH in a dog during internal fracture fixation, possibly caused by isoflurane inhalation anesthesia. We describe the case here.