Objective To investigate hepatitis B virus surface antign (HBsAg) quantitative value quantitatively in serum of chronic hepatitis B virus (HBV) infection patients with different clinical stages,at the same time,to explore the correlation between HBV DNA,patient's age and HBsAg quantitative values.Methods Collected 774 cases without antiviral treatment of chronic HBV infection from our hospital,according to the clinical features,divided cases into six groups:chronic HBV carrier group (102 cases),inactive HBsAg carrier group (211 cases),hepativis B virus e antigen (HBeAg) positive chronic hepatitis B group (236 cases),HBeAg negative chronic hepatitis B group (114 cases),HBeAg positive hepatitis B cirrhosis group (52 cases),HBeAg negative hepatitis B cirrhosis group (59 cases).Used chemiluminescence immunoassay particles analysis to determine HBsAg quantitative value in serum in patients,used real-time fluorescent quantitative polymerase chain reaction method to determine HBV DNA quantitative value in patients,and then compared differences among groups.Results HBsAg quantitative value from high to low respectively were chronic HBV cartier group,HBeAg positive chronic hepatitis B group,HBeAg negative chronic hepatitis B group,inactive HBsAg carrier group,HBeAg negative hepatitis B cirrhosis group,HBeAg positive hepatitis Bcirrhosis group,the median quantitative value of HBsAg were [7.80 (6.69-8.32),7.11 (5.42-8.27),6.57 (5.66-7.53),6.38 (4.39-7.40),6.22 (4.84-6.91),6.13 (5.48-7.01)] ; positive correlation was found between HBsAg quantitative value and HBV DNA in HBeAg positive chronic hepatitis B group and HBeAg negative chronic hepatitis B group (r =0.714,0.390,P ＜ 0.01); negative correlation was found between HBsAg quantitative value and age in chronic HBV infection(r =-0.416,P ＜ 0.01) ; Monitored HBsAg quantitative value of inactive HBsAg carriers after the age 40 had important clinical value.Conclusions HBsAg quantitative value is different in the various phases of chronic HBV infection.HBV DNA levels and age are related with HBsAg quantitative value.HBsAg quantitative value should be monitored in inactive HBsAg carriers after the age 40.