Background:The VITROS 3600 (Ortho Clinical Diagnostics, Johnson & Johnson, Buckinghamshire, UK), which uses the enhanced chemiluminescence immunoassay, has recently been introduced; however, it has not been evaluated for detection of HBsAg in Korea. We evaluated the ability of the VITROS 3600 for detection of HBsAg, compared with the ARCHITECT i2000 (Abbott Laboratories, Abbott Park, IL, USA), which is used widely in Korea to help in selection of an analyzer for detection of HBsAg. Methods:A total of 800 samples were tested randomly for HBsAg and 150 samples with positive HBV DNA detected by real-time PCR were used in this study. Precision, agreement, and Pearson correlations between two analyzers were evaluated. Results:The total standard deviations (SD) were 0.016 and 0.183 for the negative and positive HBsAg controls, respectively; the precision met the criteria suggested by the manufacturer. There were 100% agreements for the 800 random samples (positive 33, negative 767) and 150 samples with HBV DNA (positive 148, negative 2) between two analyzers. In addition, good correlation was observed between two analyzers for the 767 HBsAg negative samples (r=0.691, P=0.004), and 148 HBV DNA positive samples (r=0.763, P<0.001). Conclusion:The VITROS 3600 showed good precision and agreement. And, correlation between the VITROS 3600 and the ARCHITECT i2000 was excellent. Therefore, this result will be helpful in selection of an analyzer for detection of HBsAg.