The influence of some basic parameters of an electrolytic system on the effectiveness of the treatment of landfill leachates is investigated. The controlling parameters of the system examined were: (i) the leachate input rate, (ii) pH and temperature, (iii) the amount of electrolyte ( NaCl) added, (iv) the voltage applied and ( v) the concentration of Fe2+ (added as FeSO4 . 7H(2)O). The performance of the system was assessed in terms of the COD, BOD5 and NH4+ reduction in the leachate samples as well as in terms of the energy consumption of the system (i.e., kWh consumed per kg of COD removed). These two parameters are referred to as the optimization parameters of the system. By implementing a 2(6) factorial experiment, linear models, which interrelate each optimization parameter with the controlling parameters of the system, were generated. Using these models, effective treatment of landfill leachates by electrochemical oxidation can be designed.