Hepatocellular carcinoma (HCC) is the most common and lethal type of primary liver cancer, frequently arising from chronic liver injury and inflammation. Despite treatment advancements, HCC prognosis remains poor, emphasizing the need for effective preventive and therapeutic strategies. This study investigates the hepatoprotective and anti-tumor effects of Hongjam, a steamed freeze-dried silkworm powder, in a diethylnitrosamine (DEN) and thioacetamide (TAA)-induced HCC mouse model. Mice were administered DEN intraperitoneally for 8 weeks, followed by TAA in drinking water for 9 weeks, with Hongjam supplementation (0.01, 0.1, and 1 g/kg) provided daily through food. Hongjam markedly reduced the tumor incidence, the size, and the histological lesions compared to the DEN/TAA group. Serum biochemical analysis revealed reduction in liver damage markers, including alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, and total bilirubin, with a notable decrease in total bilirubin surpassing. Immunohistochemical and Western blot analyses demonstrated that Hongjam downregulated expression of proliferation markers, including Ki67, phosphorylation of protein kinase B, and proliferating cell nuclear antigen, while upregulating the pro-apoptotic protein Bcl-2-associated X protein, indicating its dual role in suppressing proliferation and promoting apoptosis. Furthermore, Hongjam inhibited angiogenesis by suppressing the expression of key markers, including interleukin 6, VEGF, hypoxia-inducible factor-1 subunit alpha, platelet-derived growth factor subunit beta, matrix metalloproteinase-2, and cluster of differentiation 31, thereby disrupting the tumor microenvironment. These findings suggest that Hongjam exerts multifaceted protective effects against HCC by targeting proliferation, apoptosis, and angiogenesis pathways, while also mitigating liver damage. This study highlights the potential of Hongjam as a functional food or a complementary therapeutic agent for HCC prevention and management.