To detect the expression level and clinical significance of centromere protein I (CENPI) in hepatocellular carcinoma (HCC) and to preliminarily explore the effects of on the biological behavior of liver cancer cells and its possible molecular mechanisms. The TCGA database, real-time fluorescent quantitative polymerase chain reaction, Western blot, and immunohistochemical staining experiments were used to analyze and detect the expression differences of CENPI in liver cancer and adjacent tissues. The correlation between CENPI expression levels and clinical pathological features were analyzed in combination with clinical data from HCC patients. The value of in the diagnosis and prognosis assessment of HCC was explored by plotting receiver operating characteristic curves and Kaplan-Meier survival curves. Furthermore, we investigated the impact of overexpression on the migration and healing capabilities of liver cancer cells using Transwell and wound healing experiments. Finally, the effects of CENPI on the epithelial-mesenchymal transition process in liver cancer cells and the potential molecular mechanisms were explored using Western blot. Comparisons between two groups were analyzed using -tests, and comparisons among multiple groups were analyzed using one-way ANOVA. The expression of CENPI and its correlation with clinical pathological features were analyzed using the test. The TCGA database analysis showed that the expression level of was significantly higher in liver cancer tissues than adjacent tissues, which was further validated by real-time fluorescent quantitative polymerase chain reaction, Western blotting, and immunohistochemical staining experiments. Combined clinical data analysis from HCC patients demonstrated that high expression of CENPI was positively correlated with the degree of tumor malignancy, T stage, and disease prognosis. The Kaplan-Meier survival curve indicated that the 5-year survival rate was significantly lower in patients with high expression compared to those with low expression. The results of the receiver operating characteristic curve further indicated that the expression level of had accurately predicted the prognosis of liver cancer patients (area under the curve=0.962). Transwell and wound healing experiment results indicated that overexpressing CENPI in Hep3B and Huh7 cells significantly increased cell migration numbers and healing rates. Further research results showed that overexpressing significantly upregulated the expression of mesenchymal cell-related marker genes: N-cadherin, Vimentin, and Snail protein, while the expression of the epithelial cell-related marker gene E-cadherin was significantly reduced. The mechanistic study revealed that when was overexpressed, the MEK and ERK phosphorylation levels and the expression of RAS protein were significantly increased compared to the control group, and the difference was statistically significant. The high expression of in the tissues of HCC patients is associated with poor prognosis, potentially promoting the migration of liver cancer cells and the epithelial-mesenchymal transition process by activating the RAS/MEK/ERK signaling pathway axis, suggesting that the gene may be a promising target for HCC treatment.