A lignocellulose ester catalysis method for preparing zinc sulfate from alkylation waste sulfuric acid is as below: adding alkylation waste sulfuric acid to zinc oxide or zinc hydroxide for reaction until a pH value is in a weak acid range to obtain a mixed solution; filtering the mixed solution to obtain leaching residue was and a reaction solution; then adding a catalyst of lignocellulose ester and an oxidant in the reaction solution to conduct a redox reaction; completely converting the organic matters in the alkylation waste sulfuric acid into CO2, H2O, N2 and other innocuous small molecules; conducting solid-liquid separation to obtain a fibrous residue and a purified liquid; and finally crystallizing the refined liquid to obtain a zinc sulfate product with industrial grade or feed grade purity. The lignocellulose ester not only has a catalytic function, but also has the function of an activating oxidant and adsorption decoloration; the production process does not introduce other impurities, and does not cause secondary pollution; the organic matters in the waste acid is completely oxidized and degraded; all the mother liquor is reused; and product quality is not affected.