Abstract: Objective To investigate the value of imaging examination in assessing the surgical resectability of hilar cholangiocarcinoma. Methods Radiographic data including CT and MRI of fortythree patients pathologically and surgically diagnosed as hilar cholangiocarcinoma were analyzed retrospectively. These data were as follows： the size of tumor， the length of invaded bile duct， the involved extent of portal vein and hepatic artery， the state of lymph node metastasis and distant metastasis and the involved scope of bile duct. Moreover， these cases were classified and staged respectively according to the criteria of improved “proposed Tstaging” system， which were studied statistically concerning the relevance to surgical resectability. Results The resectability in infiltrating tumor cases was 8.3％， and that of massforming cases was 51.6％（P=0.017）. The size of hilar cholangiocarcinoma and the length of involved bile duct measured by CT and MRI respectively had no influence on resectabilities（P＞0.05）. The resectabilities in cases of various Bismuth types were not statistically different（P＞0.05）. On the contrary， the resectabilities with various “proposed Tstaging” types were statistically distinct （P＜0.01）， which declined with higher Tstaging and the differences were significant（P＜0.01）. Conclusion The resectability of infiltrative tumor cases is lower than cases of massforming tumors. Both the size of mass and the length of involved bile duct are not relevant to the resectability of carcinoma. The improved “proposed Tstaging” system is superior to Bismuth classification system in assessing the resectability of hilar cholangiocarcinoma.