The invention discloses a preparation method and catalytic application of a Silicalite-1 single crystal-coated nanopalladium-loaded core-shell catalyst, and belongs to the field of novel catalytic materials. The preparation method comprises the following steps: under the hydroxyl action between 3-aminopropyl triethoxysilane and the surfaces of Silicalite-1 molecular sieve nanocrystals, modifying amino groups onto the surfaces of the molecular sieve nanocrystals; then, through coordination and complexation actions between the Pd<2+> and the amino groups modified on the outer surfaces of the Silicalite-1, uniformly and fixedly loading the Pd<2+> onto the surface of a nanocrystal molecular sieve to form the palladium-loaded nanocrystals Pd/Silicalite-1; finally, adding the Pd/Silicalite-1 nanocrystals into a synthesis solution of Silicalite-1 molecular sieve single crystals, and synthesizing the Pd@Silicalie-1 single crystal-coated core-shell catalyst via induced growth. By the preparation method, preparation is simple and high in efficiency, and the defects that the conventional catalyst is poor in monodispersity, is required to be roasted for multiple times and takes a long time for crystallizing or posttreating a sample are overcome. Compared with the traditional homogeneous catalyst, the core-shell catalyst has the characteristics of excellent shape selectivity, metal loss resistance, high temperature aggregation resistance and the like, so that the core-shell catalyst has a wide application prospect.