Hepatitis B vaccination requires 3 injections within 6 months, i.e., the ”0, 1, 6 program” is used for injection. One month after the first injection, about 30% of people produce hepatitis B surface antibody; after the 3rd injection, about 90%-95% of people produce hepatitis B surface antibody; 1 month after the 3rd injection, the antibody titer reaches the highest peak Therefore, it is important to check whether surface antibodies are produced in the 7th month after hepatitis B vaccination. However, the level of antibody produced after hepatitis B vaccination gradually decreases over time, so it is necessary to check the surface antibody of hepatitis B in 5 years, and those whose titer of hepatitis B surface antibody is less than 10 international units/mL need to receive a booster injection to complete the 3 doses of “0, 1, 6 program”. Hepatitis B vaccination. If the hepatitis B surface antibody has dropped significantly close to the detection line, a booster shot of hepatitis B vaccine can be given.