Breastmilk is the most ideal natural food for infants, containing all the nutrients and a variety of immunologically active substances needed for the growth and development of infants from 4 to 6 months, which not only suits the nutritional needs of infants, but also reduces the occurrence of infections, asthma and other diseases, and plays an irreplaceable role in the growth and development of infants. However, can a mother infected with hepatitis B virus breastfeed her baby? The answer to this question depends on the condition of the mother and the newborn. Whether or not the mother can breastfeed, the newborn should be properly immunized. The 2010 Chronic Hepatitis B Guidelines state that newborns of HBsAg-positive mothers should receive hepatitis B immune globulin (HBIG) at a dose of ≥100 IU as early as possible (preferably 12 h after birth) within 24 h after birth, and 10 μg of recombinant yeast or 20 μg of Chinese hamster oocyte (CHO) hepatitis B vaccine at different sites. Newborns of HBsAg-negative mothers can be immunized with 5 μg or 10 μg of yeast or 10 μg of CHO hepatitis B vaccine; children who have not been vaccinated with hepatitis B vaccine in the neonatal period should be given catch-up yeast (5 μg or 10 μg) or CHO hepatitis B vaccine (10 μg). Hepatitis B vaccine is given in 3 doses, and the 1st dose should be followed by the 2nd and 3rd doses at 1 month and 6 months respectively. The significance of hepatitis B vaccination is to prevent hepatitis B virus infection by making the body of the newborn produce antibodies against the hepatitis B virus. Although HBsAg and HBV DNA can be detected in the breast milk of HBV-infected pregnant women, and some scholars believe that cracked nipples, excessive sucking or even biting of nipples by infants may transmit the virus to infants. However, these are all theoretical analyses and lack evidence-based medical evidence. More evidence shows that breastfeeding does not increase the risk of hepatitis B virus infection even in HBeAg-positive pregnant women. The 2010 Guidelines for the Management of Chronic Hepatitis B clearly state that newborns can receive breastfeeding from HBsAg-positive mothers after they have received HBIG and hepatitis B vaccine within 12 h of birth. Therefore, after formal prophylaxis, newborns can be breastfed regardless of whether the mother is HBeAg positive or negative, and there is no need to test for HBV DNA in breast milk. Newborns can be immunized against the hepatitis B virus after formal prophylaxis, but the effects of antiviral medication during breastfeeding still need to be considered. For breastfeeding mothers, the decision to administer antiviral therapy should be made primarily from the perspective of the condition. If the mother is already on antiviral therapy with nucleoside (acid) drugs before breastfeeding and has not met the criteria for stopping the drugs when she enters the breastfeeding period, these patients should continue antiviral therapy, considering that stopping the drugs too early may cause hepatitis recurrence, which will affect the mother’s health. If the previous liver function was normal for a long time and hepatitis activity occurred during breastfeeding, antiviral therapy should also be considered if antiviral pointers are available. When the mother is on antiviral therapy, the newborn can be switched to artificial feeding, considering that the drug still has a certain concentration in the breast milk. In summary, whether a woman with hepatitis B can breastfeed or not cannot be generalized, but needs to be determined in the context of the newborn and the mother’s condition. First of all, regardless of whether or not breastfeeding is possible, the newborn should be given formal prophylaxis. If the mother is diagnosed as not needing antiviral treatment, she can breastfeed her newborn. However, if the mother is diagnosed as needing antiviral treatment, the newborn can be artificially fed, taking into account the effects of the drugs in the breast milk.