The invention discloses resin for a cover plate and a preparation method of the resin. The preparation method comprises the following steps: according to weight percentage, adding 10 percent to 15 percent of low-density phenolic resin and then adding 74 percent to 80 percent of a solvent by stirring; then, adding 8 percent to 12 percent of PVB (Polyvinyl Butyral) resin into a solution obtained by the step A by stirring, and heating and raising the temperature to 50 DEG C to 60 DEG C; finally, keeping the heat and stirring for 3h to 6h to obtain the resin. With the adoption of the method disclosed by the invention, the solid content of the prepared resin is 18 percent to 20 percent, the viscosity is 800mPa.s to 2000mPa.s, and the peel strength is more than or equal to 13N/cm. The resin disclosed by the invention contains a certain amount of the low-density phenolic resin, so that the resin has good heat resistance, the preparation time of the resin can also be effectively shortened, and the production efficiency is improved; meanwhile, thermosetting resin is added, so that a residual threadlike matter on a drill pin is avoided in a utilization process, and the drilling utilization quality of a product is ensured; furthermore, the PVB resin is added, so that the bonding strength of the resin can be effectively enhanced, and the reliability of the product is ensured.