The electrochemical reduction of 2-(4’-hydroxybenzeneazo)benzoic acid (I) has been studied at pyrolytic graphite electrodes in the pH range 2.0-10.4. The cyclic voltammetric behaviour clearly indicated an ECE mechanism in acidic medium in which the two-electron two-proton reduction of I gives the hydrate derivative. The acid catalysed disproportionation of the hydrazo intermediate was also studied in the pH range 2.0-6.0 and the value of k’/[H+] was found to be 1.4 x 10(-2) 1 mol(-1) s(-1) The products of the reduction have been isolated and characterized using IR, melting point, mass and related techniques.