Hepatitis B surface antigen quantification is the quantitative value of the surface protein of the hepatitis B virus, which reflects the body’s infection with the hepatitis B virus. Hepatitis B surface antigen is a protein on the surface of the hepatitis B virus, which is not infectious, but when it is present, it can indicate the presence of the hepatitis B virus in the body, and the hepatitis B virus is infectious and may be transmitted to others. Hepatitis B surface antigen quantification is an indicator relative to hepatitis B surface antigen characterization, which can only reflect the presence or absence of hepatitis B virus infection in the body, but hepatitis B surface antigen quantification can express the amount of hepatitis B virus in numerical form, which is a guide to the diagnosis of the disease as well as the subsequent use of medication. If the quantitative hepatitis B surface antigen is out of the reference range, it is necessary to consult a physician in time and take timely treatment and other measures under the guidance of the physician in conjunction with other indicators of the hepatitis B virus.