The invention relates to the technical field of isosorbide deep processing, and particularly discloses a preparation method of crystalized isosorbide. The method comprises the steps that solid isosorbide is adopted as a raw material, a solid acid molecular sieve is adopted as a catalyst, a fusion method is adopted for preparing an isosorbide reaction solution; the reaction solution is diluted and filtered to obtain filtrate an d filter residues; the filter residues are adopted as a catalyst to be recycled; the filtrate is an isosorbide mixing solution, a decoloration ion removal and mixture separation device is used for processing the isosorbide mixing solution, and then concentration, normal temperature aqueous phase process crystallization and drying are performed to obtain crystalized isosorbide. The content of the crystalized isosorbide is 98% or above. The preparation method of the crystalized isosorbide has the advantages of being simple in technological process, small in equipment investment, low in operation cost, free of acid-base and activated carbon consumption, and the like.