Abstract: The purpose of this study is to prepare galactosyl modified lipid bilayer-coated mesoporous silica nanoparticles (GPEM) to enhance the antitumor efficacy against hepatocellular carcinoma cells. The irinotecan (CPT-11) loaded mesoporous silica nanoparticles (MSNs) was coated with the Gal-P123 modified functional lipid bilayer by thin-film dispersion method. Nanoparticles were characterized with particle size, zeta potential, morphology and drug release in vitro. Afterwards, the cell uptake, intracellular concentration of CPT-11, cell apoptosis rate and cytotoxicity were evaluated on human hepatocellular carcinoma cell line Huh-7. The results showed that MSNs were coated with intact lipid bilayers and the nanoparticles had clear core-shell structure. GPEM is stable with the mean particle size of (78.01±2.04) nm. The low leakage rate in normal physiological conditions in vitro is contributed to the protection of stable lipid bilayer, and the fast drug release in acid environment due to the destruction of the lipid bilayer. On the cell level, the vector could improve the intracellular CPT-11 concentration by 4 times because of the functional lipid bilayer. The high CPT-11 concentration led to the increasement of apoptosis rate by 48.6%, and the reduction of half maximal inhibitory concentration (IC₅₀) values of CPT-11 by 2 times, indicating stronger cell cytotoxicity.