RNA interference (RNAi) is an innate antiviral plant immunity that inhibits viral genes and reduces viral infection. To activate this systemic protection, double-stranded RNA (dsRNA) derived from the viral genome and artificially synthesized can be used. Proteins such as Dicer-like ribonucleases (DCLs), Argonaute (AGO) proteins, dsRNA-binding proteins (DRBPs), and RNA-dependent RNA polymerase (RDR) are at the heart of RNAi-based antiviral plant system. Noncoding RNAs (ncRNAs) protect plants from virus-induced stress by either directly targeting the virus’s genetic material or indirectly modulating plant defense pathways. Small noncoding RNAs (sncRNAs) are the most varied category, having a length of 20–31 nucleotides and including small interfering RNAs (siRNAs), microRNAs (miRNAs), and trans-acting siRNA (tas-iRNA). By capitalizing on this system, experts have been able to develop transgenic crops that can resist multiple virus and viroid types, such as rice stripe virus (RSV), tobacco mosaic virus (TMV), and citrus exocortis viroid (CEVd). While dsRNAs have been used successfully to generate resistance, there are still barriers to the application, such as dsRNA delivery reliability and off-target effects. This chapter covers the potential use of RNAi to inhibit viral infection in crops, including mechanism and virus-resistant crops produced by RNAi approach.