There is no experimental research proving that hepatitis B vaccine will not be infected after two injections. Whether a person will still be infected by hepatitis B virus after two injections of hepatitis B vaccine depends on whether the titer of antibody against hepatitis B virus in the body is sufficiently high, and the titer of antibody is mainly related to the time of vaccination, the dose of vaccination (the number of injections) and the constitution of an individual, but has nothing to do with the number of times of vaccination. Some people will produce antibodies after the first injection, some people will produce antibodies after the second injection, some people will produce antibodies after the third injection, and even some people still do not produce antibodies after three injections. It is recommended that patients strictly follow the procedure of hepatitis B vaccination, and after receiving all the three injections of the vaccine, they should have the quantification of the surface antibody of hepatitis B in 1-2 months to see whether they have produced effective immunity and antibody titer. immunization and the antibody titer. If no antibody is produced, it means that there is a possibility of being infected, and if a sufficient amount of antibody is produced, infection by the hepatitis B virus can be avoided. When the vaccination fails and the quantitative value of Hepatitis B antibody is low, relevant examination should be carried out to clarify the specific cause and then targeted treatment, such as continuing to vaccinate a dose of booster vaccine, etc. If necessary, contact a specialist to consult the solution.