In this research, electrocoagulation-intensified peroxidation using an aluminum electrode was studied as a post-treatment method for poultry slaughterhouse wastewater (SWW) with 4 operational variables (pH, current density, contact time, and H2O2 dosage). Optimization was carried out using response surface methodology. Analysis of variance was used to analyze the experimental data, and a second-order model was created to test the effects of process parameters on treatment performance. The optimum conditions were chosen as follows: pH 5.83, 0.18 g/L H2O2 dosage, 58.60 min contact time, and current density of 4.21 mA/cm2. The compatibility of the predicted optimum conditions has been verified by experimental data. As a result of the experiments performed under optimum conditions, COD, TSS, and color removals were found to be 97.89, 99.31, and 98.56, respectively. The difference between experimental and predicted values was found to be less than 0.86. The final treated effluent met the discharge standards determined by the World Bank, EU, US, and Malaysian Department of Environment. Under optimum conditions, the cost of treating 1 cubic meter of SWW was calculated as 3.02 MYR ( 0.68). © 2023, The Author(s) under exclusive licence to Iranian Society of Environmentalists (IRSEN) and Science and Research Branch, Islamic Azad University.