Objectives To construct a hepatoma di rected gene delivery system which could transfer presantisense RNA to liver cancer cells specifically, and to explore a new therapeutic strategy for hepatocellular carcinoma by blocking hepatitis B vi rus(HBV)with antisense RNA targeting hepatocellular carcinoma. Methods GE7 and HA20 were synthesized and mixed with pEBAF-as-preS2, a heDatocarcinOma specific HBV antisense expression vector, to construct a novel HBV antisense RNA delivery system named AFP-enhancing 4-element complex Nude mice bearing hepatocelluar carcinoma cells HepG2 2 1 5 were injected with AFP-enhancing 4-element complex via a tail vein Total RNA from tissues was extracted, and reversal transcription-ploymerase chain reaction(RT-PCR)was used to detect the expression of preS2 Different doses of AFP-enhancing 4-element complex was injected into nude mice at different time points, and tumor diameter was measured. Results AFP-enhancing 4-element complex was constructed successfully RT-PCR showed preS2 antisense RNA delivered by AFP-enhancing 4-element complex only expressed in liver tumor HepG2 2 1 5 cells of the mice After the treatment of AFP-enhancing 4-element complex with dose of 0 2 ug per mouse(once a week for 4 weeks), the mean tumor diameter of nude mice was significantly shorter than that of the control groups(0.995