The invention discloses a preparation method of a catalyst for producing levoglucosenone. The preparation method comprises the following steps: S1, crushing a biomass raw material, fully mixing the crushed biomass raw material with a KOH activator according to a mass ratio of 4:1 to 1:4, adding the obtained mixture into a reactor, and carrying out a pyrolysis reaction under the protection of nitrogen to obtain biochar; S2, mixing the biochar obtained in S1 with concentrated sulfuric acid, sulfonating the biochar in a hydrothermal kettle, cooling the hydrothermal kettle, washing the obtained reaction product with deionized water to be neutral, and drying the washed reaction product in a drying oven to obtain sulfonated carbon; and S3, impregnating the sulfonated carbon to load metal ions, and performing washing and drying to obtain the metal sulfonated carbon catalyst. The invention also discloses the catalyst for producing levoglucosenone. The catalyst loaded with metal ions can effectively promote the conversion of the biomass raw material to a dehydration intermediate in the pyrolysis process, and also enhances the activity of strong acidic sites of the sulfonated carbon in orderto dehydrate the intermediate into the levoglucosenone.