Abstract: [Objective]To investigate the clinical value and epidemiology of joint detection results of HCV-cAg, HCV-Ab and HCV-RNA content and analyze its correlation with the level of alanine aminotransferase (ALT). [Methods] In 100 hepatitis C patients with HCV-RNA positive hepatitis C, the levels of ALT, HCV-cAg, HCV-Ab and HCV-RNA were detected by Rate of enzyme method, ELISA, CLIA and FQ-PCR respectively. Then the results were analyzed with statistical methods.[Results] In 100 patients with HCV-RNA positive, HCV-Ab positive rate was 97% and HCV-cAg positive rate 83%.The result of correlation analysis showed that HCV-cAg detection rate increased with the increased HCV-RNA virus content, and HCV-RNA carrier content had a positive correlation with the abonormal rate of ALT. HCV-RNA and HCV-cAg presented consistency.The results of correlation analysis also showed that the HCV-RNA carrier content had a positive correlation with the abnormal rate of ALT(P<0.05). But there was no correlation between the change of ALT value and HCV-RNA content (P > 0.05).[Conclusion] HCV-Ab detection could reflect the body's immune status to HCV infection, while it only indirectly confirmed HCV infection. The detection of HCV-RNA reflected changes in an early stage with high sensitivity and specificity, which directly reflected the virus duplication and infectivity. HCV-RNA and HCV-cAg presented consistency. HCV-RNA carrier content had a positive correlation with the abnormal rate of ALT. Accordingly, application of the three test methods at the same time could result in accurate diagnosis of HCV infection, predicting whether it was infectious, and associated with ALT could predict and evaluate liver damage and drug efficacy effectively.