The electrochernical oxidation of several 1-arylthioglycosides has been studied by cyclic voltammetry in acetonitrile. We found that the oxidation potential of the alpha anomer always occurs at a less positive oxidation potential than of the beta anomer. The difference in the oxidation potential depends on the substituent attached on the C-3 of the sugar moiety and is greatly influenced by the stability of the radical cation obtained after the first electron transfer.