RNA helicases are ATPases that are capable of rearranging RNA and ribonucleoprotein (RNP) structure, and they can potentially function in any aspect of RNA metabolism. The RNA helicase gene family of plant genomes is larger and more diverse than genome families observed in other systems and provides an ideal model for investigation of the physiological importance of RNA secondary structure rearrangement in plant development. Numerous plant RNA helicases are associated with a variety of physiological functions, but this review will focus on the thirteen RNA helicases associated with the metabolism of aberrant and silencing RNAs. The results emphasize the crucial role RNA helicase activity has in the regulation of mRNA quality control and gene expression in plant development.