In operations of the lower extremities in elderly patients, regional anesthesia is preferred over general anesthesia because regional anesthesia is associated with less deep vein thromboses, pulmonary emboli, bleeding, transfusion volume, and can better control post-operative pain. During surgery, a drop in core temperature frequently occurs. In elderly patients, temperature control and compensatory abilities are physiologically impaired. During induction of regional anesthesia, such as spinal anesthesia, elderly patients often do not complain of coldness, despite the decrease in the core temperature. Also, problems associated with hypothermia can easily be overlooked because anesthesiologists are less concerned about measuring the body temperature of patients than they are during induction of general anesthesia. Because perioperative hypothermia can cause various complications, such as infection, bleeding, cardiac injury, and shivering, closer attention is necessary. We report a case of hypothermia that developed during total hip arthroplasty under combined spinal-epidural anesthesia.