The specific timing of BCG vaccination needs to be determined by the physical status of infants and children, and cannot be generalized. BCG vaccine is a national class I vaccine for the prevention of tuberculosis in China, and the incidence and severity of tuberculosis will be significantly reduced after vaccination. For healthy newborns, the first dose of BCG vaccine is usually given within 24 hours after birth, and then reviewed after 3 months to check the effect of BCG vaccination, and if the result of tuberculin test is still negative, then another vaccination is required. For low weight premature infants and newborns with other diseases, BCG vaccination should be postponed appropriately and given after they have recovered, but it must be done within a year. Although BCG vaccination can effectively prevent tuberculosis, you should not blindly vaccinate your child, but you need to follow the doctor’s advice and regulate the operation after examination in the pediatric department or related departments of a regular hospital.