The boron-doped diamond (BDD) electrodes with different boron concentrations have been tested as electrode material for sulphamerazine (SRM) oxidation in water solution. An investigation of the electrode morphology and molecular structure was carried out using high resolution scanning electron microscopy (SEM) and Raman spectroscopy. Electrochemical results showed clearly that the kinetics and efficiency of sulphonamide oxidation were dependent on the amount of boron incorporated in a diamond film. The mechanism of sulphonamide oxidation was also analysed by cycle voltammograms and by identifying oxidative species (•OH radicals) which take part in the degradation process. The aging of the material during the operation was also studied.