A theoretical interpretation of the mechanism of ethylene glycol oxidation to glyoxal over Ag-containing catalysts is considered. A model system, reflecting the interaction of Ag cluster with process adsorbates and/or intermediates, is proposed. Both partial oxidation of ethylene glycol to glyoxal and CO2 formation routes are reconstructed, and the corresponding reaction profiles are represented. The roles played by the most important reaction intermediates participating in the process under consideration are discussed. (C) 2014 Elsevier B.V. All rights reserved.