Abstract: The plant cuticle is the first protective barrier between plants and their environment, with the main function being protection against water loss. This important biological function and the mechanistic analysis of water permeability of cuticles will provide a new scientific basis for the development of modern agriculture and the application of biomimetic materials. This article summarizes studies of chemical composition and structure of various plant cuticles to reveal the relationships between biological characteristics of the cuticle and water permeability as well as possible models showing the water pathways across cuticular membranes. The prospects of the cuticle related to water permeability are discussed, as well as its applications.