Abstract: Objective To evaluate hepatitis B virus large surfsce protein(LHBs) in monitoring of antiviral treatment.Methods LHBs.HBV serum markers and HBV DNA loads in 46 patients with adefovir dipivoxil(ADV) therapy were monitored for the whole course(60 weeks).Enzyme linked immunosorbent assay(ELISA),time differentiate immunofluoresence assay and real.time polymerase chain reaction(RT-PCR)were performed to detect LHBs,HBV serum markers and HBV DNA loads,respectively.And correlation analysis was also performed.Results Both LHBs and HBV DNA declined during the ADV treatment.and the correlation coefficient was 0.97.but LHBs declined after HBV DNA.There were 20 patients with HBV DNA<5×102/mL at 60th week.in which 8 were LHBs negative;in 14 recurrent patients,the HBV DNA turned to negative and became positive again,3 with negative LHBs;while in 12 patients resistant to the ADV therapy.2 were LHBs negative.Conclusion Dynamic monitoring of LHBs is useful in the evaluation of antiviral treatment.