Organophosphate compounds, which are essential ingredients of pesticide, plasticizer, air fuel, and chemical warfare agents, are serious neurotoxic hazardous materials. Therefore, diverse physical-chemical treatments have been attempted to degrade organophosphate compounds. In the present work, we propose a two-stage chemical and enzymatic treatment system. As a first stage, pretreatment of oxidation and coagulation using Fenton’s reagent utilizing iron and hydrogen peroxide was employed. Preferentially, 1 mM ethyl parathion (EP) pesticide was largely (~80%) removed by Fenton’s reagent reaction within 15 min. To remove residual EP, enzymatic treatment with organophosphorous hydrolase (OPH) from recombinant Escherichia coli was employed as a second stage. We successfully demonstrated that the proposed two-stage hybrid treatment process removed 1mM environmental toxic EP efficiently (~98%) within 30 min.