The electro-oxidation of Cr(III) to Cr(VI) species at the reconstructed Au(100) electrode has been investigated in a highly alkaline solution. The subsequent comparison of the results obtained with those at Au(111) electrode points to the structural sensitivity of this oxidation process related to different adsorbability of OH- anions on both electrodes. Finally, it was found that the addition of Cr(III) ions does not shift the reconstruction peak to less positive values of potential indicating that for Au(100) electrode the oxidation process under consideration has no impact on the lifting of the surface reconstruction.