The traditional Hepatitis B virus markers "HBV M"" have been used in clinic for many years. But it can not meet the clinical need for this disease any longer. Lots of reports have indicated lack of serum targets for the diagnosis of HBeAg(-) hepatitis and evaluation of the hepatitis treatment. It is urgent to find new markers which can hint the virus reproducibility, especially the easily-handled and cheap ones. The results acquired from our Large Protein Pre-S Antigen Diagnostic Kit is highly accord with DNA results, so the Pre-S Antigen is a new virus reproducibility marker.