Hepatitis B vaccine second dose is given to newborn babies at full term, Hepatitis B vaccine needs to be given at 0, 1 and 6 months of age. According to the National Immunization Program’s immunization procedures for children, the second dose of Hepatitis B vaccine should be given at 1 month of birth, i.e. at full term. Hepatitis B vaccine is mainly used to prevent hepatitis B virus infection. Generally, the first injection of BCG and hepatitis B vaccine is given within 24 hours of birth, and a total of three injections are needed, which are given at the age of 0, 1 and 6 months respectively. Only 30% of the population can produce hepatitis B surface antibody after the first injection, about 90% of the people can produce antibody after the second injection, and as many as 96% of the people can produce antibody after the three injections, and the antibody is maintained at a high level. Parents are advised to strictly follow the level of planned immunization in order to improve the immunity level of newborns and control infectious diseases.