〔Abstract〕 Objective To investigate the effect of tripartite motif containing 59(TRIM59) on the biological function of human colorectal cancer HCT116 cells and its possible mechanism. Methods The recombinant TRIM59 interference plasmid(si-TRIM59) was constructed and transfected into colorectal cancer cell line HCT116 by liposome transfection. The transfection efficiency was verified by RT-qPCR and Western blot. The effects of TRIM59 gene silencing on the proliferation, colony-formation ability and cell cycle of colorectal cancer cells were detected by CCK-8 method, colony formation assays and flow cytometry respectively. Western blot was used to detect the expression level of CDK4 and cyclinD1.Results The expression levels ofTRIM59mRNA and protein in colorectal cancer cells were significantly higher than those in normal colorectal mucosa cells(P<0. 05). After knockdown of TRIM59expression, the proliferation activity and colony forming ability of HCT116 cells were significantly inhibited(P<0. 05), and the cell cycle was arrested in G0/G1 phase. At the same time, the expression levels of CDK4and CyclinD1 significantly decreased(P<0. 05).Conclusion TRIM59was highly expressed in colorectal cancer cells. Down regulation ofTRIM59expression can inhibit the proliferation and clone formation of colorectal cancer cells, suggesting thatTRIM59may become a new target for gene therapy of colorectal cancer.