A negative hepatitis B surface antigen means that the body is not carrying the hepatitis B virus. Hepatitis B surface antigen is the outer shell protein of the hepatitis B virus, which itself is only antigenic and not infectious. Hepatitis B surface antigen negative has the following conditions, including the virus is cleared and the virus is cleared to produce antibodies, as follows: 1, the virus is cleared: when the hepatitis B surface antigen negative, hepatitis B core antibody positive, indicating that once infected with the hepatitis B virus, but the hepatitis B virus has been cleared, not carrying the hepatitis B virus, meaning that it has not become a chronic carrier of the hepatitis B virus 2. Antibody production after virus clearance: If the hepatitis B surface antigen is negative, the hepatitis B core antibody is positive and the hepatitis B surface antibody is positive, it means that the body may have been infected with the hepatitis B virus, but the hepatitis B virus has been cleared and protective antibodies have been produced and the body is immune to the hepatitis B virus. Once the hepatitis B virus reappears, the body can clear the hepatitis B virus, thus preventing infection with the hepatitis B virus and not causing liver damage.