According to research, HBsAg-positive mothers infect their babies during delivery, which is an important transmission route for hepatitis B. Moreover, 40% to 70% of babies born to HBsAg-positive mothers will become chronic HBsAg carriers. If the mother is HBsAg-positive and also HBeAg-positive (referred to as double-positive), then the mother’s infection rate to the baby during childbirth is even higher, up to 90% or more. These chronic HBsAg carriers can not only become a source of infection in the society, but also develop chronic hepatitis, and some patients die of liver cancer on the basis of cirrhosis. Therefore, it is important to interrupt the transmission of hepatitis B virus between mother and child. The specific methods are as follows: if the mother is double positive for HBsAg and HBeAg, one injection of hepatitis B immunoglobulin within 6 hours and one month after birth, and then 20ug of hepatitis B vaccine at 2, 3 and 6 months; if the mother is single positive for HBsAg, 20ug of hepatitis B vaccine can be injected within 24 hours and 1 and 6 months after birth, with good statistical results. The protection rate for infants can be over 95%.