The invention provides a treatment method for peroxide di(2,4-dichlorbenzoyl) wastewater. The treatment method comprises the following steps: heating peroxide di(2,4-dichlorbenzoyl) wastewater; regulating the pH value of the obtained wastewater to be lower than or equal to 2 with hydrochloric acid to perform acid separation; performing primary solid-liquid separation on the obtained material to obtain a solid material which is 2,4-dichlorobenzoic acid, regulating the pH value of the obtained liquid material to be 5-7 with a sodium hydroxide solution, and sequentially performing concentration and secondary solid-liquid separation to obtain the solid material which is sodium chloride. The treatment method provided by the invention does not lead in other impurity ions, and is simple in operation; meanwhile, no other wastewater is generated in a treatment process, treatment pressure of a wastewater treatment system is greatly relieved, treatment cost is reduced, and the environment is favorably protected.