NOVELTY - Treatment of pesticide sewage involves introducing sewage into ammonia separation column, deaminating, steaming, blowing gas, absorbing gas in sulfuric acid, oxidizing, mixing liquid in separation column with low-concentration ammonia-nitrogen sewage, introducing the mixture into floatation device, removing suspended solids and oil droplets, oxidizing resultant sewage, separating, mixing low-salt low-chemical oxygen demand domestic sewage with the mixed sewage solution, introducing mixed sewage into a biological reaction system, and performing anaerobic treatment.    USE - Treatment of pesticide sewage produced during production of chlorpyrifos, dichlorvos, phoxim and isocarbophos pesticides (all claimed).    ADVANTAGE - The pesticide sewage is economically treated by simple process.    DETAILED DESCRIPTION - Treatment of pesticide sewage involves adjusting pH of high-concentration sewage to 11-12 using 30 %mass caustic soda, introducing pH adjusted sewage into ammonia separation column, deaminating, steaming at more than 85 degrees C, blowing gas, absorbing gas in sulfuric acid, oxidizing using sodium hypochlorite solution, mixing liquid in ammonia separation column with low-concentration ammonia-nitrogen sewage, introducing the mixture into floatation device, removing suspended solids and oil droplets, mixing oxidizing agent and resultant sewage, oxidizing obtained mixture in combined oxidation reactor (I) and phosphorus oxidation reactor (I), and combined oxidation reactor (II) and phosphorus oxidation reactor (II), respectively, performing solid-liquid separation, recycling solid, adjusting pH of liquid to 3-4, breaking the liquid in an oxidative destruction reactor which cause destruction to cyclic bonds of pyridine rings or benzene rings, adjusting pH of obtained mixed sewage solution to 6-9, mixing low-salt low-chemical oxygen demand (COD) domestic sewage with the mixed sewage solution, introducing mixed sewage into a biological reaction system, performing anaerobic treatment such that refractory organic molecules are converted into low-molecule organic material and organic nitrogen is converted to inorganic nitrogen, introducing resultant sewage into anoxic/aerobic bioreactor, processing, discharging effluent, and filtering resultant sludge.