AIM: To investigate the clinical value of T-staging system in the preoperative assessment of hilar cholangiocarcinoma.METHODS: From March 1993 to January 2006, 85 patients who had cholangiocarcinoma diagnosed by operative tissue-biopsy were placed into one of three stages based on the new T-staging system, and it was evaluated the resectability and survival correlated with T-staging.RESULTS: The likelihood of resection and achieving tumor-free margin decreased progressively with increasing T stage (P ＜ 0.05). The cumulative 1-year survival rates of T1, T2 and T3 patients were 71.8%,50.8% and 12.9% respectively, and the cumulative 3-year survival rate was 34.4%, 18.2% and 0%respectively; the survival of different stage patients differed markedly (P ＜ 0.001). Median survival in the hepatic resection group was greater than in the group that did not undergo hepatic resection (28 mo vs 18 mo;P ＜ 0.05). The overall accuracy for combined MRCP and color Doppler Ultrasonagraphy detecting disease was higher than that of combined using CT and color Doppler Ultrasonagraphy (91.4% vs 68%; P ＜ 0.05 ). And it was also higher in detecting port vein involvement (90% vs54.5%; P ＜ 0.05).CONCLUSION: The proposed staging system for hilar cholangiocarcinoma can accurately predict resectability,the likelihood of metastatic disease, and survival.A concomitant partial hepatectomy would help to attain curative resection and the possibility of longterm survival. MRCP/MRA coupled with color Doppler Ultrasonagraphy was necessary for preoperative evaluation of hilar cholangiocarcinoma.