Objective: To investigate the expression of interferon-induced transmembrane protein 3 (IFITM3) in hepatocellular carcinoma (HCC), and its significance. Methods: The protein expression of IFITM3 along with matrix metallopeptidase 9 (MMP-9) in 60 specimens of HCC and paired cancer adjacent tissues were determined by immunohistochemical staining and Western blot analysis. IFITM3 small interfering RNA fragments (psilencer3.1-shIFITM3) were constructed and transfected into HCC HepG2 cells, and after transfection, the changes in mRNA and protein expressions of IFITM3 and MMP-9, proliferative capacity, as well as invasion and migration ability of the HepG2 cells were examined by qRTPCR, Western blot, CCK8 assay, and Transwell and scratch wound-healing assay, respectively. Results: Both positive expression rate and expression level of IFITM3 and MMP-9 protein expressions in HCC tissue were significantly increased compared with cancer adjacent tissue (positive expression rate: 81.67% vs. 13.33%; 88.33% vs. 8.33%, all P<0.05); in HepG2 cells after psilencer3.1-shIFITM3 transfection, both IFITM3 and MMP-9 expression were decreased at either mRNA or protein level, proliferation rate and the number of invaded cells were reduced, and wound closure was significantly delayed. The differences in all quantitative parameters had statistical significance (all P<0.05). Conclusion: IFITM3 expression is increased in HCC, and the high expressed IFITM3 may promote the proliferation, invasion and migration of HCC cells through regulating MMP-9 expression.