The number of doses required for hepatitis B vaccination depends on the value of the surface antibody of the two pairs of half after vaccination, as follows: 1. If the value of hepatitis B surface antibody is 0mIU/ml after three doses of vaccine, you should follow the standard course of treatment again, and receive one dose of vaccine at 0, 1 and 6 months, a total of three doses. 2. If the surface antibody value is above 10mIU/ml, but less than 100mIU/ml, it means that the protection is not particularly strong, so it is recommended that another vaccination be given to strengthen the surface antibody value above 100mIU/ml.