The invention relates to a preparation method of resin having high-efficiency adsorption effect on patulin. By taking polysaccharide as a raw material, the polysaccharide resin is prepared through the procedures of adsorption, dispersion, emulsification, pre-crosslinking, crosslinking, elution, modification and the like. The polysaccharide resin prepared by the invention has the characteristics of short production cycle, simple preparation process, uniform product specification, low cost and the like, and is suitable for industrial production. The polysaccharide resin product prepared by the invention is white or light yellow, uniform in particle size, good in quality, safe and non-toxic, can be used for adsorption of patulin in the fields of fruit juice, beverage and the like, and effectively solves the problem of patulin overdose, thus having favorable application prospects.