Objective To compare the detection rate of Anti-hepatitis C virus (anti-HCV) with chemilumines- cence immunoassay (CLIA) and enzyme immunoassay (EIA)，and explore the clinical significance of CLIA in diagnosis of HCV infection. Methods The anti- HCV in 6461 patient samples were detected by CLIA and EIA respectively，and anti - HCV positive samples were confirmed with HCV- RNA test. Results The positive rate of anti-HCV in 6461 patient samples determined by CLIA and EIA were 3. 17% and 2. 86%，respectively. The positive coincidence ratio of CLIA detection confirmed by HCV RNA assay (97. 1% ) was obviously higher than that of EIA (91. 9% ) . Among EIA detection samples，while S ： CO value was more than 5. 0，the positive coincidence ratio confirmed by HCV RNA was 100% . In weak positive samples，the positive coincidence ratio was only 69. 7%. Among CLIA detection samples，while S ： CO value was more than 2. 0，the positive coincidence ratio confirmed by HCV RNA was 100% . In weak positive samples，the positive coincidence ratio was 92. 9% . 31 anti- HCV positive samples detected by CLIA were negative detected by EIA. 4 anti - HCV positive samples detected by EIA were negative detected by CLIA. Conclusion CLIA provides higher specificity and positive predictive value than EIA，and reduces false- positive results. It is effective laboratory procedures for early diagnosis and treatment monitor of hepatitis C vims infection with CLIA.