The treatment of petroleum wastewater was studied using the electrocoagulation process with aluminum and iron electrodes aiming to simultaneous removal of sulfide and COD. All affecting parameters, such as solution pH, applied current density, time of electroprocessing, electrode material and addition of surfactant, were investigated. Sulfide was rapidly and effectively removed using iron electrodes. The removal of COD was effectively effectively enhanced by performing the electrocoagulation process after addition of the surfactant polyethylene glycol oleate.