Abstract: Apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3G (APOBEC3G) is a kind of natural anti viral factor, the present study has proved that it has the function of anti HBV. It can affect the reverse transcription of HBV DNA, induce HBV DNA super mutation, pack it into the HBV virus particles, participate in the antiviral effect of interferon and other ways to resist hepatitis B virus. It has opened up a new direction for the development of new antiviral drugs and the study of mechanism of natural immune system, which may provide new clues for the prevention and treatment of HBV in the future.