Hepatitis B virus DNA quantitative test is a blood test performed as a criterion to determine whether a patient with hepatitis B has viral replication. If a patient’s viral replication is less than 500 copies/mL, it indicates low or no viral replication in the patient’s body. At this time, the patient should further check the liver function to see if there is any elevation of glutamic acid and glutamic oxalacetic aminotransferase, and if there is any elevation of bilirubin. If not, the patient should be regularly observed and rechecked every six months or a year for hepatitis B DNA, ultrasound, liver function, coagulation function, AFP, etc. In addition, with the development of detection technology, many hospitals can now perform accurate quantitative examination of hepatitis B virus, with a detection domain value of up to 20 IU/UL, so that the hepatitis B virus can be detected even in a low replication state, and then combined with other test results to determine the patient’s condition and decide whether antiviral treatment is needed.