Abstract: Objective:To investigate the clinical efficacy of extended hepatectomy for hilar cholangiocarcinoma (HCCA) of Bismuth-Cor -lette types Ⅲand Ⅳ(the longitudinal invasion degree along the biliary system is the main criteria). Methods:The clinical data of 61 patients with HCCA of Bismuth-Corlette types III and IV admitted in the Department of Hepatobiliary Surgery of the First Affiliated Hos-pital of Bengbu Medical College from January 2008to May 2015were analyzed retrospectively. Among the61cases, 22underwent hepatectomy with half or over half of the liver removed or hepatic caudate lobectomy (regarded as the extended hepatectomy group), whereas39cases underwent irregular hepatectomy on the hepatic hilar region (regarded as the limited hepatectomy group). Results: Compared with those in the limited hepatectomy group, the patients in the extended hepatectomy group underwent longer duration of operation and experienced more bleeding during the procedure. The complication incidence rate for the extended hepatectomy group was lower than that for the limited hepatectomy group. No patient died during the perioperative period in the extended hepa -tectomy group, whereas two patients died in the limited hepatectomy group. Moreover, R 0 resection was performed on 21cases in the extended hepatectomy group, with a resection rate of (21/22) 95. 5%, and on20cases in the limited hepatectomy group ( P<0. 05), with a resection rate of ( 20/39) 51. 3%. Actuarial 1-, 3-, and 5-year survival rates were 77. 27%, 36. 36%, and 13. 64%, respectively, in the extended hepatectomy group, and 69. 23%,20. 51%, and 1. 64%, respectively, in the limited hepatectomy group (P<0. 05). Conclusion: Extended hepatectomy for patients with HCCA of Bismuth- Corlette types Ⅲand Ⅳcould effectively increase the resection rates of R0 and the survival rate. Meanwhile, the prognosis of patients could be improved.