The electrochemical oxidation process of 2-halogenoderivatives: 2-chloro-2'-deoxy- adenosine (2CldAdo), 2-bromo-2'-deoxyadenosine (2BrdAdo) and 2'-deoxyadenosine (2'dAdo) has been studied in aqueous buffered solutions by DPV and CV using a glassy-carbon electrode. All compounds investigated exhibit one-step electrochemical oxidation in the pH range 2-9. Macroelectrolyses at the potential corresponding to DPV oxidation peaks have been performed in acetate buffer (pH 4.5) using a pyrolytic graphite electrode. While oxidation of 2BrdAdo occurred with elimination of Br-2, no liberation of Cl atom was found for oxidation of 2CldAdo. The oxidation products of the compounds investigated have been examined by UV spectroscopy, electrochemical and HPLC analysis. The mechanism of electrochemical oxidation of halogenated deoxyadenosines is proposed.