Hepatitis B virus quantification can be detected for relatively high viral loads and may not be detected for very low viral loads. Hepatitis B virus quantification, also called hepatitis B DNA test, is a test to detect the amount of virus in the body of hepatitis B patients. Hepatitis B virus quantification has a certain reference range, ordinary reagent reference range is less than 100, if below 100 may not be detected, above 100 can be detected. The reference range of high-precision hepatitis B virus quantification is less than 10, most of the patients with hepatitis B virus can be detected through high-precision test. If the hepatitis B virus in the patient’s body if very small, less than 10, there is a possibility that it will not be detected. Hepatitis B patients need to follow up the quantitative hepatitis B virus test regularly.