Catalysts containing Au deposited on Fe3O4 (commercial Cerac) and on Fe2O3 were synthesized, characterized by XPS, XRD, Mössbauer spectroscopy, H2TPR, isopropanol decomposition – a probe reaction of acid-base properties, and tested in oxidation of CO and C3H8. Au//Fe3O4 cat a lyst, containing a mixture of magnetite and maghemite (gamma-Fe2O3) phases, was found to be more acidic containing more surface OH groups and less reducible than Au/alfa-Fe2O3 (hematite). The activity in oxidation of CO and propane was higher for Au/alfa-Fe2O3 catalyst as compared with Au/Fe3O4.