Abstract: Hepatocellular carcinoma (HCC) is the most common primary liver cancer and is a significant cause of cancer-related death throughout the world. Therefore, studies investigating cellular mechanisms of HCC areessential for developing effective therapies. As we all know, the Ras/Raf/Mek/Erk signaling pathway is a high-ly conserved module that extensively participates in cell growth, proliferation, differentiation, apoptosis, andmigration. The Ras/Raf/Mek/Erk signaling cascade is one of numerous MAPK signal transduction pathways that are frequently deregulated in tumourigenic diseases. In addition, aberrant activation of the Ras/Raf/Mek/Erk pathway has been shown to be involved in the pathogenesis and progression of HCC. Mutation of the Ras gene and the overexpression of growth factors including EGF, VEGF, PDGF and the homologous mem-brane receptors result in aberrant activation of the Ras/Raf/Mek/Erk pathway, which in turn induces abnormalproliferation, invasive growth and metastasis of HCC. In this manner the Ras/Raf/Mek/Erk pathway partici-pates in and promotes the pathogenesis and progression of HCC. Therefore, inhibition of Ras/Raf/Mek/Erksignaling may be an effective therapy for HCC.