Abstract: Objective To study the correlation between expression of hilar cholangiocarcinoma(HCCA)-associated proteins,microvessel density(MVD) and clinocopathological characteristics of HCCA. Methods Expressions of HCCA-associated gene products,including Her-2,P170,VEGF,mutant P53,Ki-67,and Top-Ⅱα in 75 HCCA patients were detected with immunohistochemitry SP method.Vascular endothelial cells were marked with CD34 antibody.MVD was measured and its correlation with pathological characteristics of HCCA was analyzed.Effect of Ki-67 and Top-Ⅱα on proliferation of HCCA cells was detected with Kappa and Kruskal-Wallis method,respectively. Results Protein Her-2(21.7%),P170(51.2%),VEGF(36%) and mutant P53(48.8%) were detected to express in the specimens,respectively.Ki-67(93.3%) and Top-Ⅱα(83.7%) were also detected to express in the specimens,and there was a good concordance between Ki-67 and Top-Ⅱα in detecting the proliferation of tumor through Kappa analysis(P=0.001).The expression rate of MVD was significantly lower in well-differentiated adenocarcinoma than in moderately and poorly differentiated adenocarcinoma(P<0.05),while no significant difference was observed in MVD expression between moderately and poorly differentiated adenocarcinomas(P>0.05). Conclusion The expression of HCCA-associated proteins is closely related with the MVD and pathological characteristics of HCCA and can be used as an index in assessing the biological characteristics of HCCA.The effect of Ki-67 and Top-Ⅱα expression is similar on proliferation of HCCA.