Functional human hepatocytes xeno-engrafted in mouse liver can be used as a model system to study hepatitis virus infection and vaccine efficacy.Significant liver xeno-repopulation has been reported in two kinds of genetically modified mice that have both immune deficiency and liver injury-induced donor hepatocyte selection: the uPA/SCID mice and Fah-/-Rag2-/-Il2rg-/-mice.The lack of hardy breeding and the overly elaborated technique in these two models may hinder the potential future application of these models to hepatitis virus infection and vaccination studies.Improving the transplantation protocol for liver xeno-repopulation from human hepatocytes will increase the model efficiency and application.