Hepatitis B immunoglobulin is for intramuscular injection only and should not be used for intravenous injection. It is mainly used for hepatitis B prophylaxis. It is suitable for mothers and infants born to hepatitis B surface antigen-positive mothers, accidentally infected people and people in close contact with hepatitis B patients and hepatitis B virus carriers. Immunoglobulins for hepatitis B are essentially hepatitis B surface antibodies that enable the body to rapidly acquire passive protective immunity, work rapidly in the short term, neutralize and clear free hepatitis B virus from the serum, and avoid localized infection with hepatitis B virus. Infants born to hepatitis B surface antigen-positive mothers need a dose of hepatitis B vaccine and hepatitis B immune globulin within 12 hours of birth; it takes some time for the hepatitis B vaccine to produce hepatitis B surface antibodies, and hepatitis B immune globulin is needed for protection during the window period. For people who are accidentally infected with hepatitis B virus and those who are in close contact with hepatitis B patients and hepatitis B virus carriers, if they do not have hepatitis B surface antibodies themselves, they also need a timely injection of hepatitis B immune globulin to prevent hepatitis B virus infection and a hepatitis B vaccination to promote the production of hepatitis B surface antibodies.