The invention relates to a load type polymeric acidic ionic liquid catalyst and a preparation method and application thereof, and belongs to the technical fields of catalysis, materials and chemical industry. The catalyst comprises granules which are dispersed on the surface of a porous carrier and contain ionic liquid, the loading capacity of the acidic ionic liquid of the catalyst ranges from 2% to 10%, and for the catalyst, the specific surface area measured through a specific surface area and micropore adsorption analysis meter ranges from 250 m<2>/g to 350 m<2>/g. The load type polymeric acidic ionic liquid catalyst and the preparation method and application thereof have the advantages that the loaded ionic liquid content of the catalyst is high, and the catalytic esterification effect is good; under a specific reaction device and reaction condition, the yield of catalytically synthesizing dimethyl succinate can reach 85%.