Hepatitis B core antibody of 30 needs to be combined with other indicators to determine whether it is serious. If the hepatitis B DNA level is high and the liver function is abnormal, then it is more serious, if the hepatitis B DNA is normal and in recovery, then it is not serious. Hepatitis B core antibody positivity has many situations, if hepatitis B core antibody positivity is accompanied by high hepatitis B virus DNA content and abnormal elevated liver function, it generally suggests that the virus is actively replicating and is more serious. However, if only hepatitis B core antibody is positive and hepatitis B virus DNA is normal, it may suggest that the hepatitis B infection is recovering, which is relatively not serious, and regular review can be done. Generally, the diagnostic significance of hepatitis B core antibody positivity alone is not significant, and it is recommended to carry out further relevant tests to determine whether other items are negative or positive, as well as quantitative hepatitis B DNA, etc., in order to understand whether it is infectious.