Optimal safety for a donor is an essential condition for living-related liver transplantation (LRLT). Severe pulmonary embolism may be a rare complication for the donors, but it is potentially fatal. Various risk factors and prophylactic methods for thromboembolic complications have been described. We report here a case of severe pulmonary embolism in a living-related liver transplantation donor who underwent right liver lobectomy, although the patient had no apparent risk factor for thromboembolism except for slight obesity (body mass index = 27). In addition, the donor received prophylactic use of graduated compression stockings and intermittent pneumatic compression by use of a special device from the start of anesthesia until the patient was able to ambulate. Fortunately, the patient was successfully treated with urokinase and heparin infusion followed by warfarin administration.