The human body relies on its own immunity to clear the virus, which is the main force of anti-hepatitis B virus, and the existing anti-hepatitis B virus drugs play an assisting and facilitating role, so the application of anti-viral drugs must seize the appropriate time to achieve the effect. HBV infection can be divided into four periods: immune tolerance period, immune clearance period, inactive HBsAg carrier state, and a few patients may have reactive period. The immune tolerance period is long for mother-to-child transmission and early childhood HBV infection, during which HBV DNA levels are high and HBeAg is positive, but ALT and AST are at normal levels for a long time, during which treatment with existing antiviral drugs often fails to achieve the expected results, Although HBeAg is still positive, if the amount or relative quantification can be measured, it is lower than the tolerance period, which is the best period for antiviral therapy. The immune clearance period is the goal of current treatment if antiviral therapy is effective, HBeAg changes from positive to negative, anti-HBe negative to positive, HBV DNA drops <105 cps/mL, ALT and AST return to normal, and the person enters inactive HBsAg carrier status. Most people can be stable for a long time during this period, a few patients may enter the reactive phase, it has two situations, one is due to the virus for a long time under immune pressure, the virus appears pre-C and C promoter mutation, gradually into HBeAg negative chronic hepatitis B, the second is HBeAg re-positive, this time ALT and AST rise, HBV DNA>105 cps/mL, again need antiviral treatment. Therefore, for inactive HBsAg carriers, liver function, HBV DNA quantification, AFP and ultrasound of liver and spleen should be rechecked every six months under the long-term supervision of a doctor, just in case.