The invention relates to the field of papermaking and discloses a preparation method of hydrophobic oilproof paper. The preparation method includes: 1), making body paper: soaking bleached softwood chemical pulp, and pulping; mixing the bleached softwood chemical pulp, carboxymethyl cellulose, bacterial cellulose and dissolving pulp, making handsheet, and drying to obtain the body paper; 2), dissolving a natural polyhydroxy high molecular material in water, stirring, heating, holding temperature until a system is transparent, stirring, cooling to room temperature to obtain coating liquid, andcoating; 3), drying the body paper after being precoated, using an acyl chloride solution to treat the surface of the body paper, and drying to obtain a finished product. The problem that paper is porous is solved by means of coating the surface of the paper with the polyhydroxy high molecular material which is natural and easy to degrade, and an acyl chloride compound not containing fluorine is used to replace fluorine-containing polymer to endow the paper with hydrophobicity and oilproofness, so that environment friendliness is realized. In addition, paper prepared by the method has good strength performance and printability.