Background: To clarify significance of the present National Clinical Database risk calculator (NCD-RC) for hepatectomy in Japan, relationship between perioperative parameters or outcomes in major hepatectomy and the mortality rate by NCD-RC was examined. Methods: Patient demographics, co-morbidity, surgical records, postoperative morbidity or mortality were examined and compared to the 30 days- or in-hospital-mortality rate among 55 patients with hepatobiliary diseases who underwent hemi- or more-extended hepatectomy and central (segment 458) hepatectomy. The cut-off percent for high risk mortality before hepatectomy was set at 5% in this period. Results: In-hospital morbidity over CD III was 17 (28%), The 30-day mortality and in-hospital mortality was nil and two (3%), respectively. Male patient showed significantly higher in-hospital mortality rate (p<0.01). In the 37 patients (group woML), mean age was 67.8±8.7 years old ranging 45 and 84. Others included A) with severe complications or mortality in whom low mortality rate (group wML, n=13), B) without severe complications neither mortality in whom high mortality rate (group woMH, n=7), and C) with severe complications or mortality in whom high mortality rate (group wMH, n=4 (6.5%)). Age, distribution of elderly patients, gender, the hepatobiliary diseases and the prevalence of preoperative co-morbidity were not significantly different between groups. In the group wML, the bile leakage was dominant and, however, the in-hospital death was not observed. In the group wMH, all operations were right hepatectomy with bile duct resection (RH-BDR) for biliary malignancy and two died of hepatic failure and, however, the prevalence of RH-BDR was not significantly higher in comparison with other groups. Conclusions: Predictive mortality rate by risk calculator under nationwide survey did not always match with patient outcomes in the actual clinical setting and further improvement will be required. In case of RH-BDR for biliary malignancy with high predictive rate, the careful perioperative managements is important under the present nationwide database.