Hepatitis B is an infectious disease caused by the hepatitis B virus with hepatitis as the main manifestation. It is transmitted in various ways, and adults are also susceptible to infection when exposed to the hepatitis B virus. Hepatitis B can be transmitted through blood, body fluids, mother-to-child transmission, sexual contact, and contact with broken skin and mucous membranes. China is a country with a high prevalence of hepatitis B. Mother-to-child transmission is the most important transmission route for hepatitis B in China, and it is estimated that 40% to 50% of infected people are infected by mother-to-child transmission, but this does not mean that they will not be infected with hepatitis B as adults. Hepatitis B virus may be present in the blood, semen and saliva of hepatitis B patients, and the higher the amount of virus, the more infectious it is. If one of the spouses or friends has hepatitis B, he or she may pass it on to the other person through sexual contact, kissing, eating and other close contacts in daily life, or a healthy person may get infected with hepatitis B by accidentally touching the blood of a hepatitis B patient through a break in the skin. The reason why we have the incorrect view that hepatitis B is mostly inherited from parents is that about 90% of hepatitis B infections in infants and children will become chronic and become slow hepatitis B patients, and some slow hepatitis B patients will also develop cirrhosis and liver cancer; while in adults, more than 90% of hepatitis B infections in adults are acute and can be cured by themselves. Self-healing, many people even do not have any symptoms, hepatitis B two pairs of half test performance for hepatitis B surface antigen negative, hepatitis B virus core antibody, surface antibody and e antibody positive, some people only appear hepatitis B virus e antibody and or core antibody positive. Therefore, hepatitis B can be transmitted through a variety of ways, adults are also susceptible to infection, but the infection is mostly manifested as an acute process, even without any symptoms, and can be self-healing.