〔Abstract〕 Objective To investigate the expression of mannose binding lectin 2(MBL2) in hepatocellular carcinoma(HCC) cell lines and its effects on the proliferation and prognosis. Methods MBL2 expression levels in patients of different sexes and survival analysis of patients were subsequently performed using bioinformatics method.The mRNA and protein expression levels were detected with the qRT-PCR and Western blot.Cell proliferation was examined by MTT assay and cell clone formation assay; Flow cytometry was used to detect the cell apoptosis and cell cycle.Gene set enrichment analysis(GSEA) was used to analyze the signal pathways of MBL2 enrichment. Results Bioinformatics analysis and qRT-PCR results showed that MBL2 was highly expressed in male HCC patients compared with female HCC patients, and was related to the prognosis of HCC patients.Compared with the control group, over-expression of MBL2 inhibited the viability and clone formation rate of Huh7 cells and MHCC-97H cells; In addition, cell cycles were arrested and cell apoptosis increased.GSEA and Western blot results showed that MBL2 was enriched in the cell cycle signal pathway.Overexpression of MBL2 inhibited the expression of CDK4 protein and promoted the expression of P16 and BAX protein. Conclusion The expression of MBL2 is down regulated in HCC,which is related to the prognosis of male patients with HCC and participates in the process of cell proliferation.MBL2 may be a potential therapeutic target for male patients with HCC.