CONSIDERING HIGH WATER CONSUMPTION IN THE PULP AND PAPER INDUSTRY, LARGE AMOUNTS OF WASTEWATER IS GENERATED. AS A RESULT, IN ORDER TO PREVENT THE RELEASE OF CONTAMINANTS INTO THE ENVIRONMENT AND ALSO PROVIDE CONSUMING WATER REQUIRED BY THE INDUSTRY, WASTEWATER TREATMENT IS OF GREAT IMPORTANCE. ELECTRO-COAGULATION IS AN EFFECTIVE TECHNIQUE FOR TREATMENT OF PULP AND PAPER INDUSTRIAL EFFLUENT. IN THIS STUDY, A BATCH ELECTRO-COAGULATION (EC) REACTOR USING SIX IRON PLATES AS ANODES AND CATHODES WITH MONO-POLAR CONFIGURATION HAS BEEN INVESTIGATED FOR TREATMENT OF PAPER RECYCLING WASTEWATER. USING EXPERIMENT DESIGN METHODS, FIFTEEN TESTS WERE CONDUCTED TO INVESTIGATE THE EFFECTS OF THE OPERATIONAL PARAMETERS INCLUDING APPLIED CURRENT DENSITY, INITIAL PH, AND TREATMENT TIME ON THE CHEMICAL OXYGEN DEMAND (COD) REMOVAL EFFICIENCY. FINALLY, A COD REMOVAL EFFICIENCY OF 64 % (PREDICTABLY 65.91%) WAS OBTAINED UNDER THE OPTIMUM CONDITIONS OF CURRENT DENSITY: 130 A/M2, INITIAL PH: 7.27 AND TREATMENT TIME: 68.03 MIN. THE COLOR REMOVAL EFFICIENCY OF 84.84 % WAS OBTAINED UNDER THESE CONDITIONS.