Objective In order to study the biological function of Fas and Fas ligand system, discuss the feasibility of treating tumor with transfecting FasL gene. Methods the rat Fas ligand complementary DNA was subcloned to retroviral vector pLXSN, acquired pLXSN/FasL+ recombinant with direct inserting and single copy,then packaged with PA317 amphotropic packaging cells,anti-G418 clones were acquired,and it was named PA317/ pLXSN-FasL+ cells.Results The titer of virus was 4.7×107 CFU/ml,there was FasL gene integration in PA317/pLXSN-FasL+ cells detected by polymerase chain reaction. When we used the supernatant of the PA317/pLXSN-FasL+ cells to infect hepatocellular carcinoma cells HepG-2,SMMC-7721,CBRH-7919 and RH-35 ,the FasL expression was found at all the surface of the four cell lines through FCM,and the apoptosis in HepG-2 and CBRH-7919 cells which had high levels Fas expression was found too.Conclusion the results show that it is an effective way to introduce FasL gene to retroviral vectors, which can be used to induce apoptosis in the cells with high levels Fas expression.