We retrospectively assessed the safety of the donor operation, based on parameters such as blood loss, blood transfusion, operation time, duration of hospitalization, and complications. Forty-five pediatric and adult recipients underwent living-donor liver transplantation (LDLTx) in Tohoku University Hospital from July 1991 to October 2000. Donor operations were classified into three groups. In the LS group, the graft was the lateral segment ( n=20); in the LL group, the graft was the left lobe without the middle hepatic vein ( n=16); and in the LLM group, the graft was the left lobe with the middle hepatic vein ( n=9). No significant differences were observed among the three groups regarding postoperative liver function or duration of hospitalization. In the LS group, the operation time was shorter and the requirement of autologous blood transfusion was significantly lower than in the other two groups. Most complications following retrieval of the graft were minor. Safety is guaranteed when the left lobe or the left lateral segment is used for LDLTx, but meticulous management of the operation is required to prevent complications.