The electrochemical oxidation of the 2,4-dibromoaniline in aqueous sulphuric acid solutions at concentrations higher than l.OM, at a Pt electrode, has been studied by rotating-disk electrode, cyclic voltammetry and controlled-potential electrolysis. A single oxidation process is found at acid concentrations lower than 6.5 M. At higher acid concentrations, a second oxidation process is also observed up to 12.0 M acid concentration whereupon it overlaps with the first process. Both processes are controlled either by diffusion or by adsorption depending on the tested medium. The electroactive species of the first process is always the protonated form Ar-&Hs. This species is oxidized in a two-electron step to form the (Ar-NH#+ cation. Deprotonation of this cation and subsequent hydrolysis of the resulting species gives the correspondingpbenzoquinonimine, which is further hydrolysed to bromo-pbenzoquinone. Two additional redox pairs observed in cyclic voltammograms are ascribed to the reduction equilibrium of the two last compounds. After long electrolysis times, the bromo-p-benzquinone is hydratated to the 3-bromo-1,2,4benzenetriol and a new additional redox pair found in cyclic voltsmmograms following electrolysis experiments is attributed to the oxidation equilibrium of this product. The loss of two protons from the benzenic ring of the (Ar-NH#* cation produces the electroactive species of the second process, which is bielectronically oxidized. Under diffusion control, both processes are irreversible and the corresponding initial two-electron transfer is the rate-determining step.