The electrochemical behaviour of linearalklybenzenesulfonate (LAS) on Pt electrode has been investigated in 0.05 M Na2SO4 and in 0.1 M NaCl at pH = 8 by potentiokinetic method and by electrolysis. The anodic and cathodic semilogarithmic current-potential curves were obtained between -1.6 V - +1.6 V. The experimental discharge potentials (Eexp.) have been determined by means of current-potential curves obtained by electrolysis method between 0-3 V. The percentages of surface active material remaining in solution after specified time periods (0-6 h) were determined for different initial concentrations of LAS (30, 150; 300 ppm) by using the potentiostat (+ 1.6 V) and by applying constant potentials of 20 V via a direct current source. The concentrations of LAS in solution was determined by UV spectrophometer. Results indicate that when a potential of 20 V is applied on the electrodes the concentrations of surface active materials (LAS) decreases by 40-50% at the end of 6h in 0.05 M Na2SO4 solution. (C) 1998 Elsevier Science Ltd. All rights reserved.