Objective:To develop a mouse model of acute hepatitis B virus infection and observe lentiviral vectors(LVs) with small interfering RNAs-mediated inhibition of HBV replication and expression in the model. Methods:Thirty-six Balb/c mice were randomly divided into three groups(n = 12,each). ①Negative control group(NC group):the model of acute hepatitis B virus infection were established by administrating pTHBV2(the eukaryotic expression vectors which contain HBV genome informations) through tail-vein; ②experimental group(E group): pTHBV2 and pWPT-HBV-siRNA1(the lentivirus with siRNA1 aimed directly at HBV S-sector) were administrated through tail-vein; ③independence group(I group): pTHBV2 and pWPT- HBV-siRNA2(the lentivirus with siRNA2 which didn’t aim at HBV) were administrated by the same method. The serum and liver tissue were collected on the fourth and seventh days respectively. ELISA method was used to detect HBV surface antigen(HBsAg) in serum; RT-PCR was selected to detect HBV S-mRNA level in hepatic tissue. Intracellular HBV core antigen(HBcAg) and HBsAg were determined by immunohistochemistry. Results:In contrast with NC group, serum HBsAg level in E group was decreased by 89.76% and 94.81% on the fourth and the seventh days, respectively(P < 0.01);Liver tissue HBV S-mRNA level, intracellular HBcAg and HBsAg levels were also depressed obviously(P < 0.05); whereas serum HBsAg, tissue HBV S-mRNA,intracellular HBcAg and HBsAg levels didn’t differ significantly between NC group and I group(P > 0.05). Conclusion:Based on the results of this experiment, LVs with siRNAs could remarkably inhibit the replication and expression of HBV in vivo, which augmented from the fourth day to the seventh day.