The invention relates to preparation and application of a super-hydrophobic / oleophobic coating layer with excellent performance, wherein the preparation comprises the steps: dispersing nanoparticles and cellulose in an alkaline substance-containing alcoholic solution, and adding tetraethyl orthosilicate and fluorine-containing organosilane for hydrolytic coating to form a solution A; dispersing epoxy resin in an alcoholic solution to form a solution B; uniformly mixing the solution A and the solution B, and then adding tetraethyl orthosilicate and fluorine-containing organosilane to react to generate polysiloxane, to obtain a solution C; dissolving a fluorine-containing amine compound in an alcoholic solution to obtain a solution D; and uniformly mixing the solution C and the solution D, spraying the mixture on a substrate, and curing to obtain the product. A multi-stage micro-nano hierarchical structure is constructed; the super-hydrophobic / oleophobic coating layer has good chemical stability, can achieve a complete repelling effect on N,N-dimethylformamide liquid drops (34.4 mN / m), has a contact angle of 120 degrees on n-hexadecane (27.1 mN / m), is simple in preparation method, can be sprayed on a large scale, and paves a road for industrialization of the super-hydrophobic / oleophobic coating layer.