Hepatitis B e antibody is one of the five tests for hepatitis B. It is an antibody produced by the body’s immune system in response to the e antigen of the hepatitis B virus, and its presence indicates a reduction in hepatitis B virus replication and infectivity. The hepatitis B virus is a DNA virus, and we have developed a series of serological indicators to detect the infection of the virus based on its biological characteristics, including hepatitis B surface antigen, antibody, hepatitis B e antigen, antibody and hepatitis B core antibody, commonly known as the hepatitis B two-and-a-half indicators. The e antigen is present inside the hepatitis B virus. When the hepatitis B virus infects the human body and begins to replicate, the e antigen is released into the bloodstream, at which point the five tests for hepatitis B indicate a positive e antigen, a sign that the virus is actively replicating and is infectious. The body’s immune system can then produce antibodies against the e antigen, or e antibodies, to neutralize and destroy the e antigen, inhibit the replication of the virus, block its infectiousness, so that the disease tends to recover. In addition, some mutations of the hepatitis B virus may cause the body to test positive for e antibodies but negative for e antigen, which should be combined with a test for hepatitis B virus DNA to determine the strength of hepatitis B virus replication in the body. In summary, e antibody is a neutralizing antibody produced by the body’s immune system against the e antigen inside the hepatitis B virus, and usually indicates a reduction in hepatitis B virus replication and infectivity.