Objective：To study the correlation between HBV Pre-S1 antigen, HBeAg levels and HBV DNA copies, so as to assess the clinical value of Pre-S1 in detection of HBV replication. Methods: A total of 363 HBsAg-positive samples were collected. The levels of Pre-S1 antigen, HBeAg and HBV DNA copies were determined by ELISA, time-resolved immuno-fluorescent method and real-time fluorescent quantitative PCR(FQ-PCR),respectively. The correlation between the determination results was analyzed. Results: Pre-S1 antigen level was correlated with the level of HBeAg (χ2=94.4,P<0.01), with the coefficient being 0.45; Pre-S1 antigen level was also correlated with HBV DNA(χ2=198.58, P<0.01), with the coefficient being 0.59. The positive rate of Pre-S1 increased with HBV DNA copies. When logarithm of HBV DNA copies was more than 3, the sensitivity, specificity, accuracy, positive predictive value(PPV), positive likelihood ratio(PLR) and odds ratio(OR) of Pre-S1 were 84.5%,91.2%,87.0％,94.1%,9.6，and 56.8 respectively；the numbers of HBeAg were 50.4%,94.9%，67.2％，94.2%,9.8 and 18.9, respectively. Conclusion: Pre-S1 antigen is correlated with HBV DNA and is more sensitive and accurate than HBeAg in reflecting HBV replication. The above 3 parameters can complement each other and the combination of them is more accurate in clinical diagnosis.