The surface antigen of hepatitis B is still likely to relapse after the negative, for the following reasons: a. The original chronic hepatitis B patients, after antiviral treatment, the surface antigen of hepatitis B has turned negative, but this does not fully represent the hepatitis B virus has been cleared, in the liver cells inside the cccDNA still exists, will still replicate the virus, but the degree of viral replication is very low, the test reagents can not detect, when the antiviral drugs are discontinued After stopping the antiviral drugs, the amount of virus may slowly develop from a very low level to a high level, so that the hepatitis B surface antigen turns positive again. The first thing you need to do is to get rid of the virus, but the body does not produce hepatitis B surface antibodies, there is still no immunity to hepatitis B. When exposed to the hepatitis B virus again, it is still possible to be infected by hepatitis B, and will again appear hepatitis B surface antigen positive.