The Hepatitis B vaccine is usually given in different parts of the body, such as alternating between the right and left arms. Hepatitis B vaccine is mainly used to prevent hepatitis B disease, and the injection is mainly intramuscular, the most common site is the deltoid muscle of the upper arm. The most common site is the deltoid muscle of the upper arm. Some patients are newborns, and this group of patients can be injected in the outer muscle of the front of the thigh. Hepatitis B vaccine can be injected alternately on the left and right sides, whether it is the deltoid muscle of the left upper arm or the deltoid muscle of the right upper arm, both are intramuscular injections, so the efficacy of the hepatitis B vaccine will not be affected. When injecting hepatitis B vaccine, it is better to complete the whole injection course, if only one injection will affect the production of antibodies and fail to achieve the purpose of hepatitis B prevention. Hepatitis B vaccine does not have to be injected in the same place, after three injections of hepatitis B vaccine, the quantitative test of hepatitis B penta-analysis will be conducted in two months to ascertain whether the antibody has been produced.