In Japan, where the average age of the population is increasing rapidly, control of spiraling medical costs is considered to be a crucial issue, one that requires urgent attention. The recent introduction of the diagnosis-related-group/prospective-payment-system (DRG/PPS) has attracted attention as a promising means to this end. In order to examine the feasibility of introducing DRG/PPS in the field of gastroenterological surgery, the Group of Gastroenterological Surgery of the DRG Survey and Research Committee, directed by Prof. Yoshiki Hiki, investigated the medical costs involved in treating 539 patients with cholelithiasis who were hospitalized in 11 surgical facilities in Japan (nine university hospitals, one municipal hospital, and one private hospital). In the treatment of cholecystolithiasis, the cost of laparoscopic cholecystectomy was significantly less than that of both simple open surgery and surgery converted from laparoscopic cholecystectomy. The presence of postoperative complications after cholecystectomy resulted in a significant increase in the overall cost of hospitalization, because of the need for additional injections, examinations, treatments, and hospital care. The average cost of uneventful laparoscopic cholecystectomy in the 11 facilities ranged widely, from 530, 000 yen to 930, 000 yen, in accordance with the length of hospital stay. PPS may be applicable to the benign disease cholecystolithiasis if the treatment course is standardized.