The second dose of hepatitis B vaccination should be given 1 month after the first dose, but the second dose should not be postponed for more than 2 months. Hepatitis B is a common infectious disease, and for better prevention of the hepatitis B virus, the hepatitis B vaccination should be given in a timely manner, generally requiring three doses, with the second dose being 1 month after the first dose and the third dose being the sixth month after the first dose. If the second vaccination is postponed for special reasons such as acute illnesses like fever, the postponement should not exceed 2 months, otherwise the immunization effect will be significantly affected and a new vaccination will be required. After receiving the full course of hepatitis B vaccine, it is necessary to go to the hospital to test whether the hepatitis B antibodies are positive. Positive indicates the production of hepatitis B protective antibodies, which can effectively prevent the transmission of hepatitis B virus. After hepatitis B vaccination, patients need to pay attention to their own situation, if there is fever, rash, etc., timely review and treatment, and pay attention to a light diet to avoid the occurrence of other diseases.