Hepatitis C,which is caused by HCV,is a worldwide epidemic endangering human health,and nowadays there is no specific treatment.As a novel molecule of gene therapy,small interfering RNA (siRNA) has been increasingly used to inhibit HCV infection based on the antiviral effect of RNA interference(RNAi).Some progress has been made,such as the inhibition of HCV rephcation or relevant cellular cofactors by siRNA,the prevention of escape mutants,and the rehtions between siRNA and innate immunity.Meanwhile,researchers are also facing many obstacles.In this paper,studies of inhibition in HCV infection by siRNA were briefly summarized.