Abstract: Objectives:To investigate the expression of cyclin B1 (CCNB1) in hepatocellular carcinoma (HCC)and the effect of silencing CCNB1 on hepatocellular carcinoma cells.Methods:HCC sequencing data from the databases Gene Expression Omnibus (GEO) and the Genotype-Tissue Expression (GTEx) were used to compre-hensively analyze the expression level of CCNB1 mRNA and its correlation with clinical prognosis.CCNB1 (sh-CCNB1) was silenced in Huh7 and SK HCC cell lines to detect its effect on the growth, migration, invasion and cell cycle of HCC cells.Results:Analysis of sequencing data showed that CCNB1 mRNA was significantly ele-vated in various tumor tissues and also in HCC tissues compared with normal tissues (SMD=1.69, 95% CI: 1.36-2.02, I²=96.2%).The down-regulation of CCNB1 expression in Huh7 and SK cell lines showed that compared with the control group (sh-NC group), the cell proliferation of sh-CCNB1 group was significantly inhibited, and the abilities of cell migration and invasion were significantly decreased; compared with the sh-NC group, sh-CCNB1 increased the proportion of Huh7 cells in G0/G1 phase (P< 0.05) and decreased in S phase (P< 0.05); sh-CCNB1 decreased the proportion of SK cells in S phase (P< 0.000 1) and significantly increased the propor-tion in G2/M phase(P< 0.01).Conclusion:CCNB1 is highly expressed in HCC and the silencing of CCNB1 in-hibits the growth of HCC cells.