In hepatocellular carcinoma (HCC), CD147 expression contributes to tumor malignancy; however, its relationship with the tumor-immune microenvironment (TIME) remains unclear. This study aimed to elucidate the clinicopathological characteristics associated with CD147 expression in HCC and investigate its association with the TIME, specifically its association with tumor-infiltrating lymphocytes (TILs) and oncostatin M (OSM). Using 397 HCC specimens from patients undergoing curative-intent resection, we assessed CD147 expression in tumor cells and quantified OSM-positive cells and various TILs (CD8+, CD4+, FOXP3+, and CD20+ cells) in the TIME. Using tissue microarrays, these assessments were performed through immunohistochemical analysis. We investigated the associations between CD147 expression status, the density of OSM-positive cells, and the densities of various TILs. High CD147 expression, found in 332 specimens (83.6%), was associated with advanced clinical stage (P = 0.029), fibrosis (P = 0.036), and higher densities of FOXP3+ cells (P = 0.0039), CD4+ cells (P = 0.0012), and OSM-positive cells (P = 0.0017). In CD147-high tumors, OSM-positive cell density was associated with all assessed TIL subsets (CD8+, CD4+, FOXP3+, and CD20+ cells; all Ps < 0.001), whereas in CD147-low tumors, OSM-positive cell density was associated only with FOXP3+ cells (P = 0.0004). In HCC, CD147 expression is associated with an immunosuppressive TIME, characterized by increased FOXP3+ regulatory T cells and a correlation with OSM-positive cells. These results elucidate the potential mechanisms through which CD147 facilitates tumor-immune evasion, suggesting the CD147 - OSM axis as a promising target for therapeutic intervention in HCC.