Objective: To investigate the expressions of XIAP and SMAC in cholangiocarcinoma tissues and their serum levels in cholangiocarcinoma patients and then to analyze their clinical significance. Methods: The expressions of XIAP and SMAC in cholangiocarcinoma tissues together with the tumor adjacent tissues from 54 cholangiocarcinoma patients were detected by immuneohistochemical staining, and the serum levels of XIAP and SMAC in 25 cholangiocarcinoma patients and 15 healthy subjects were determined by ELISA assay. The relations of their expressions with clincopathologic factors of the patients and the changes in their serum levels in the patients before and after operation were analyzed. Results: In cholangiocarcinoma tissues compared with their adjacent tissues, the positive expression rate of XIAP was significantly increased (81.45% vs. 30.00%, P<0.05), while the positive expression rate of SMAC was significantly decreased (38.89% vs. 80.00%, P<0.05). The XIAP expression was significantly related to the pathological classification and presence or absence of lymph node metastasis, while SMAC expression was significantly related to the TNM stage and presence or absence of lymph node metastasis (all P<0.05), and there was a negative correlation between XIAP and SMAC expression in cholangiocarcinoma tissue (r=-0.327, P<0.05). In cholangiocarcinoma patients, the preoperative serum XIAP level was significantly higher and SMAC level was significantly lower than those in healthy control subjects (both P<0.05), and both of them tended to be normal after operation. The expressions of XIAP and SMAC in cholangiocarcinoma tissue and their serum levels in these patients had significant consistency (r=0.381, P=0.025; r=0.623, P=0.000). Conclusion: XIAP expression is increased and SMAC expression is decreased in cholangiocarcinoma, and their combined detection may have certain significance for early diagnosis and estimation of therapeutic effect and prognosis of cholangiocarcinoma.