RNAi is an efficient antiviral system, and viral gene-specific siRNAs are very promising antiviral inhibitors. However, many viruses have evolved highly sophisticated mechanisms that interfere with both siRNA- and miRNA-guided silencing pathways. Deeper understanding the strategies exploited by viruses provides the basis for the development of effective RNAi-based therapies that prevent viral evading. Therefore, the latest progress on the strategies exploited by viruses for evading the RNAi is reviewed.