The kinetics of the electrochemical degradation of methomyl has been study by the means of electrochemical techniques, UV-vis spectrophotometry, HPLC, and HPLC-ESI-MS in the sodium chloride containing solution. Degradation kinetics has been investigated on the DSA Ti/RuO2 electrode in mainly 2 g dm(-3) sodium chloride solution, applying the currents in the range of 10-90 mA and methomyl concentration from 0.05 to 0.5 mM. It has been suggested that methomyl degradation initially follows the pseudo zero-order Langmuir-Hinshelwood reaction kinetics, and mixed homogeneous and heterogeneous pseudo first-order reaction during prolonged electrolysis. (C) 2013 Elsevier B.V. All rights reserved.