To elucidate the role of MRPL9 in HCC, we transfected overexpressed MRPL9 plasmid into Huh7 and HepG2 cells and found that upregulated MRPL9 could significantly promote tumor proliferation, metastasis and interfere cell cycle by promoting the transition of G1/S phase. The gene discussed is MRPL9; the disease is hepatocellular carcinoma.