The invention discloses a treatment method and device for a discharge liquid of a mechanical galvanizing process, and belongs to the technical field of mechanical galvanized wastewater treatment and recycling. According to the method, the discharge liquid of the mechanical galvanizing process is collected from a water outlet of a foundation seat pool into a collection tank; the liquid in the collection tank is pumped into an integrated water purifier; and after the liquid is subjected to a reagent-adding neutralization reaction, flocculation and clarification, and filtration and sedimentationin the integrated water purifier, clear water enters a clear water regulating pool from the integrated water purifier, sludge slurry enters a sludge dewatering machine from the integrated water purifier and is dewatered to form sludge slag, and the clear water is supplied and used for rinsing in a mechanical galvanizing plating tank and a plating solution after being subjected to reagent-adding adjustment in the clear water regulating pool. According to the method, collection, purification, adjustment and internal recycling of the discharge liquid of the mechanical galvanizing process are realized, and zero external discharge of liquids in the production process is achieved; and the processing system is simple in process, and is convenient for operation.