Objective To study HBV-infected grey marmot (marmota baibacina) generation after generation.Methods The healthy and HBV-infected marmots,which bred in the laboratory more than two monthes,were injected with the human serum containing HBV-DNA.HBV-M,HBV-DNA,and ALT/AST were observed by ELISA,PCR-ELISA,Lai's methods each week from the frist to fouth week and each month from the second to eighth month.The relative tissues were checked on pathology.The second and third generations were injected in the same way with the mixture serum,which came from the postive bodies in the first generation infected by HBV.Results\ There were good responses of the serum in the first and second generation,but no response of the serum in the third generration.Inflammatory responses of liver tissue could be found in all generations. Conclusion\ The preliminary study confirmed that it would be hopeful for grey marmot to be animal model with HBV.