After hepatitis B vaccine is injected, normal people should check the hepatitis B tri-system after one week to see whether the hepatitis B surface antibody is positive, and what is its titer after it is positive. If the titer of Hepatitis B surface antibody is more than 1000mIU/ml, the patient’s protection mechanism is stronger and there is no need to continue to take Hepatitis B vaccine. The duration of protection with hepatitis B antibody greater than 1000mIU/ml depends on the patient’s immune status and the patient’s physical condition after vaccination. If the patient has strong immunity and has not been exposed to the blood of hepatitis B patients at work, such antibodies can be preserved for a long time, usually lasting for about 5-10 years. If the patient is a medical worker, often contact with the blood or body fluids of hepatitis B patients, at this time, he/she may have hepatitis B antibody depletion, and it is recommended that the patient check the hepatitis B triple system once every 2-3 years, to see whether the hepatitis B surface antibody is positive, and the titer of the titer is high or low. If the titer of hepatitis B surface antibody is too low, you can consider to continue to strengthen the injection of hepatitis B vaccine to further enhance the level of hepatitis B surface antibody in the body, so as to avoid the infection of hepatitis B virus.