Objective:To investigate the expression of ANLN in intrahepatic cholangiocarcinoma(ICC)and explored the function of ANLN in proliferation of ICC in vivo. Methods:We used the Western blot and real-time PCR(RT-PCR)to quantify the expression of ANLN in cancerous tissues and adjacent tissues of 40 patients with ICC. The differences in the expression of ANLN in ICC and the adjacent tissues of cancer were compared,and its relationship with tumor staging and tumor size was analyzed. ANLN low expression HUCCT1 cell lines were established using small interference RNA(siRNA). The cell proliferation was investigated by cell counting kit-8 assay(CCK-8),colony formation and cell cycle arrest. In addition,the proteins that regulate ANLN expression in CCA were selected by using String,and the relationship between them was verified by Western blot and RT-PCR. Results:The results of Western blot and RT-PCR revealed that ANLN was highly expressed in ICC tissues. Clinical data analysis showed that the expression of ANLN was closely related to the tumor size and TNM stage in patients with cholangiocarcinoma,and the prognosis of patients with high ANLN expression was poor. The reduction of ANLN by siRNA could effectively inhibit the proliferation ability of cholangiocarcinoma cells. Western blot showed that the reduction of ANLN led to a significant decrease in the expressions of periodic protein cyclin D1 and cyclin A. String showed that TPX2 may play a major role in the regulation of ANLN expression,Western blot and RT-PCR further validated the positive relationship between ANLN and TPX2. Conclusion:ANLN regulates the proliferation of cholangiocarcinoma cells,which promotes the development of ICC and provides a new target for the treatment of ICC.