RNA silencing is an ancient phenomenon commonly existed in organisms, which acts as the mechanism of self-protection in defending abnormal DNA and as the gene expression regulator during the growth and development of organisms. The hotspots about RNA silencing and the methods of this technique used in plants according to its durational differences were introduced. The current status and prospective of the technique in the areas of plant functional genomics studies, improvement of crop quality, and plant breeding for virus resistance were reviewed.