The use of steatotic livers for transplantation is often associated with increased primary non-function. To reduce the risk of liver injury, steatosis of the donor liver in living donor liver transplantation (LDLT) was treated with restricted diet and exercise. A 21-year-old male donor, 167cm in height and 87kg in body weight, initially received a 1800kcal/day diet for 9 days which was then gradually reduced using a 1600kcal/day diet for 43 days, followed by a 1500kcal/day diet for one day and was finally maintained on a 1400kcal/day diet for 52 days. Daily exercise consumed 500kcal/day. The non-protein respiratory quotient (npRQ) gradually increased while the non-esterified fatty acids (NEFA) decreased during the course of the 105-day treatment. Consequently, the initial 80% steatosis was reduced to 10% and was accompanied by 13% weight loss for 81 days. The npRQ values and NEFA concentrations in the later period of dietary and exercise treatment were higher and lower, respectively, than in the early treatment period, indicating compensation through long-term treatment. Therefore, energy metabolism and NEFA levels represent important biomarkers for short-term intensive treatment by restricted diet and exercise in donors with hepatic steatosis.