Chronic HCV infection is a leading cause of chronic hepatitis and its sequelae, liver cirrhosis and hepatocellular carcinoma. Current therapeutic options are limited, associated with significant adverse effects and costly. Accordingly, there is strong impetus to develop novel therapeutic strategies that act through alternate mechanisms. RNAi has been widely used for the analysis of gene function and represents a potentially promising approach for the treatment of HCV infection. siRNAs are short RNA duplexes approximately 21 nts long. When introduced into mammalian cells, siRNA can silence specific gene expression. Although efficient suppression of HCV replicon RNA in cell culture has been demonstrated with siRNAs, there is much work to be done to improve delivery, limit off-target effects and minimize development of virus resistance. Here, we review the use of RNAi as a tool to inhibit HCV gene expression and discuss the potential advantages and obstacles for this new potential therapeutic approach against HCV infection.