Positive surface antigen of the hepatitis B virus indicates that a person is a hepatitis B patient. When the hepatitis B virus infects a person, it eats away at the liver cells and reproduces, producing large amounts of the hepatitis B virus, as well as some of the components of the hepatitis B virus, which are present in the blood circulation. What is present in the blood circulation may be the complete hepatitis B virus particles, but these large particles are relatively rare, and it is the small particles on the surface of the virus that are scattered in the blood circulation, and the most common of these small particles is the hepatitis B surface antigen. Hepatitis B surface antigen positivity is usually only seen in people infected with the hepatitis B virus. In addition to checking for hepatitis B surface antigen, you should also check for hepatitis B surface antibody, E antigen, E antibody, and core antibody, which is the complete hepatitis B penta-test, and preferably quantitatively, to be able to determine the patient’s condition in a more specific way. If it is determined that the hepatitis B virus is infecting the patient, it is also important to check the DNA quantification of the hepatitis B virus, check liver function, liver ultrasound, and alpha-fetoprotein so that the patient’s current status can be fully assessed.