Objective：To prepare the transgenic mice harbouring 2 copies genome of hepatitis B virus(HBV) as a useful model for the studies of medical issues related to HBV. Methods：The HBV(adr subtype)transgenic mice were prepared by microinjection of complate 2.0 copy HBV genome into pronuclei fertilized eggs. The PCR assay, Southern-blotting, radioimmunity, immunohischemistry and ELISA methods were used to detect the HBV intergration，expression and replication in the transgenic mice. The dane particles were observed in the liver. The pathological change was tested with ALT,AST in the serum and the normal histological slides. Results：The 4 transgenic mice were obtained and the HBV DNA can be expressed and replicated in the transgenic mice. HBV genomic DNA in mouse line could be transmitted to next generations. No evidence suggested the existence of pathogenesis. Conclusion：The HBV transgenic mice were obtained and the virus genes can be expressed, the Dane particles can be formed in the liver.The mice are tolerant to HBV gene products. The transgenic mice are similar to human chronic HBV carrier. The structure and the function of the transgenic mice are stable.