In China, mother-to-child transmission is the main route of transmission of hepatitis B. About 50%-80% of HBV infections come from mother-to-child transmission. mother-to-child transmission of HBV can be divided into intrauterine infection, intrapartum infection and postpartum infection. Intrauterine infection refers to the fetus being infected by HBV in the mother’s body during growth and development; intrapartum infection refers to the newborn swallowing maternal blood, amniotic fluid, vaginal secretions containing HBV during delivery and causing infection; postpartum infection is mainly transmitted by close contact between mother and child during life. Currently, it is believed that high HBV load in pregnant women is the main risk factor for mother-to-child transmission, and reducing viral load can reduce mother-to-child transmission. Among pregnant women with hepatitis B, HBeAg negative, their newborns by regular immunization, the protection rate has reached 98%-100%; if HBeAg positive, their newborns by regular immunization, there are still 5-15% of chronic infection. How to completely achieve the interruption of mother-to-child transmission of HBV? 1, all HBV-infected women of childbearing age for preconception screening. 2, regular maternity checkups and close monitoring: In addition to routine prenatal checkups, monthly monitoring of liver function is recommended for HBV-infected pregnant women. HBV DNA is recommended to be rechecked at 26-28 weeks of pregnancy to determine the strategy of mother-to-child blockade; HBV DNA is rechecked every 4-8 weeks during the period of taking antiviral drugs and before delivery to observe the efficacy of the treatment. For pregnant women with HBV DNA <106 copies/ml, no intervention can be made; for pregnant women with HBV DNA >106 copies/ml, oral LAM or LdT antiviral therapy can be started from 28 weeks of gestation to reduce the risk of mother-to-child transmission of HBV, with full information about the risks, weighing the pros and cons and signing an informed consent. 3. Pregnant women with HBV infection with mild to moderate abnormal liver function and no medical complications can have a trial of vaginal delivery if their liver function is normal after hepatoprotective treatment and there are no contraindications to obstetrics; if liver function continues to be abnormal, liver function and Child-Pugh classification should be fully evaluated and delivery should be ended by cesarean section at the appropriate time. In patients with compensated and decompensated cirrhosis, liver function and Child-Pugh classification should be fully evaluated to decide the timing of cesarean delivery, and it is recommended to end delivery at 33-35 weeks of pregnancy. 4. For newborns of HBsAg-positive mothers, HBIG 200 IU should be injected as early as possible after birth (preferably 12 h after birth), along with 10 μg of recombinant yeast hepatitis B vaccine at different sites, and the second and third doses of hepatitis B vaccine at the first and sixth months of life, respectively. For premature infants weighing less than 2000g, hepatitis B vaccination will not be given for the time being, but HBIG 100-200IU will be injected; when the weight reaches more than 2000g or 1 to 2 months after birth, hepatitis B vaccination will be given as appropriate. 5, breastfeeding: newborns can receive breastfeeding from HBsAg-positive mothers after HBIG and hepatitis B vaccine injection within 12h of birth. (1) HBeAg-positive mother with HBV DNA ≥ 106 copies/ml should be informed that breastfeeding may have certain risks, and if the patient chooses to breastfeed it is recommended to monitor anti-HBs level regularly; (2) the following cases are recommended to suspend breastfeeding: mother’s nipples are cracked and oozing blood; mother with abnormal liver function; newborn with oral ulcers and mucosal injury.