The invention relates to methyl parathion degradation fungus and the preparing method of the enzyme preparation thereof, and belongs to the biological high technical field. The methyl parathion degradation fungus strain is plesiomus shigelloides, and the production process of liquid enzyme preparation adopts the steps of slant culture, seed liquid shaking, seed fermenter, fermenter, bacterial collection, mechanical cell crushing, clear liquid collection, (NH4)2SO4 fractional precipitation, HEPES buffer solution suspension, dialysis, and crude enzymes production. Enzyme dry powder preparation which is easy to be stored or transported can also be further refined, and processing steps added on the basis of the crude enzymes production are as follows: DEAE-Sephadex-A50 anion column chromatography, CM Sepharose Fast Flow cation column chromatography, dialysis, cryodesiccation and enzyme dry powder production. The direct application of the liquid crude enzymes preparation can ensure the organic phosphorus pesticide residue quantity in agricultural crops to be reduced by more than 90 percent, and the residual on the surface of garden spgarden stuff washed to be reduced by about 98 percent; after the enzyme dry powder preparation is diluted according to a specific proportion, the pesticide residue quantity can be reduced by more than 95 percent. The enzyme preparation product resolves the problem that the pesticide residue is over-standard in the agricultural production.