Objective：To explore the effect of interferon（IFN-α） on expression of adenosine deaminases acting on RNA 1（ADAR1） in Huh7.5.1 cells and the regulation of ADAR1 on HCV replication. Methods：The expressions of ADAR1 were measured in Huh7.5.1 cells post-treatment by IFN-α（30 IU/mL），and the effects of IFN-α modulation were determined through addition of IFN-α following addition of infectious JFH HCV（0.2 MOI） to Huh7.5.1 cells. ADAR1 siRNA knockdown，overexpression and knockout in Huh7.5.1 cells were incorporated to testify the relation of ADAR1 and HCV replication. Results：IFN-α induced the significant expression of ADAR1 p150 on both RNA and protein level（48 h：t=10.400，P=0.007；72 h：t=19.390，P=0.002），while the level of ADAR1 p110 re－main stable（48 h：t=0.806，P=0.472；72 h：t=1.929，P=0.133），and the level of HCV RNA decreased significantly（48 h：t=10.170，P=0.001；72 h：t=35.810，P=0.000）. Overexpression of ADAR1 p110 and p150 inhibited HCV replication on the level of RNA and protein（P=0.004，P=0.015）. The replication of HCV increased by two folds after ADAR1 siRNA knockdown（t=13.530，P=0.000）. Compared to intact cells，ADAR1 knockout Huh7.5.1 cells enhanced HCV replication（t=5.259，P=0.023）. IFN-α still showed significant inhibitory effect even after ADAR1 knockdown by siRNA（t=9.146，P=0.001）. Conclusion：ADAR1 induced by IFN-α inhibits HCV replication in Huh7.5.1 cells，and ADAR1 may partially mediate the inhibitory effect of IFN-α on HCV replication.