There are many hepatitis B positive mothers in our country, and whether the babies of hepatitis B positive mothers can be breastfed is a major social issue. An analysis of 63885 mothers in Hong Kong over a 10-year period showed that the breastfeeding rate of hepatitis B positive mothers was about 10% lower than the average because of the fear of “passing” the hepatitis B virus to their babies through breastfeeding, and hepatitis B infection in mothers was the most important factor affecting the breastfeeding rate. So in the end, can hepatitis B positive mothers breastfeed? The main reason for insisting that hepatitis B positive mothers cannot breastfeed is that the hepatitis B virus can be detected in some breast milk, so there is a theoretical possibility of transmission to the child, especially when the mother has a ruptured nipple. Supporters of breastfeeding believe that breastfeeding is the best way to feed a baby has been recognized worldwide. Compared to artificial feeding, breastfed children are far less likely to have diarrhea, respiratory infections, etc., and in the long term, the incidence of allergic diseases, obesity, etc. is also lower. Therefore, the benefits of breastfeeding are real. On the contrary, the risk of infection for hepatitis B positive mothers breastfeeding is only theoretical. Although hepatitis B virus can be detected in some breast milk, there is no evidence to date that breastfeeding does increase the risk of “passing” hepatitis B virus to the baby. Several retrospective studies have shown that the rate of hepatitis B infection in breastfed babies of hepatitis B positive mothers is either indistinguishable from or lower than that in artificially fed children. The World Health Organization (WHO) recommends breastfeeding for hepatitis B positive mothers, precisely because it is not worth trying to give up the real benefits of breastfeeding for the sake of unwarranted risks. Of course there are experts who have found some theoretical explanations for why breastfeeding hepatitis B does not increase the infection rate in babies. For example, although the virus can be detected in the breast milk of some hepatitis B positive mothers, its content is much lower than that of the mother’s blood and amniotic fluid, and the majority of babies can be detected in the stomach after birth, so if breastfeeding can infect the baby, the baby should have been infected by the mother’s blood or amniotic fluid, or intrauterine infection has already occurred; another explanation is that the hepatitis B surface antigen of newborns born to hepatitis B mothers can be more than 10% positive. However, as long as the baby is injected with hepatitis B immunoglobulin and hepatitis B vaccine within 12 hours of birth, the chronic infection rate is only less than 5%, indicating that timely vaccination with hepatitis B immunoglobulin combined with hepatitis B vaccine can block the infection at birth or after birth and therefore can be breastfed. Prompt postnatal vaccination with hepatitis B vaccine and hepatitis B immune globulin is the most effective interruption of mother-to-child transmission of hepatitis B. Although the available evidence is more supportive of breastfeeding for hepatitis B positive mothers, previous studies have had different drawbacks. Because of the long-standing fear of hepatitis B, even a very, very slight risk can sway a mother to breastfeed. Therefore there is a need for very rigorous studies that provide solid and credible evidence to strengthen the confidence of hepatitis B positive mothers to breastfeed.