Gold nanoparticles supported on titania nanostructured materials were prepared, characterized and tested in CO oxidation. Two nanostructured supports were used: titania nanotubes (TNT) synthesized by the Kasuga method and titania nanotubes decorated with TiO2 anatase nanocrystals prepared by post-synthetic treatment of TNT with 0.05 M HNO3 solution at 70 degrees C for 48 h (TNT-T). Gold catalysts with 4 wt.% of Au nominal loading were prepared by deposition-precipitation with urea. A reference Au catalyst supported on TiO2 Degussa P-25 was also prepared. Supports and catalysts were characterized by N-2 physisorption, XRD, UV-vis and Raman spectroscopy, TPR, SEM-EDX and HRTEM. HRTEM characterization showed that gold nanoparticles with an average size between 2 and 7 nm were obtained in all catalysts making them suitable for CO oxidation. Catalytic tests showed differences in activity and stability among the prepared catalysts. The Au/TNT catalyst presented poor activity for CO oxidation, meanwhile the Au/TNT-T catalyst showed higher activity than the Au/TiO2 Degussa P-25, especially at a low temperature interval (-10 to 100 degrees C). Stability tests performed for Au/TNT-T and Au/TiO2 Degussa P-25 catalysts at 25 degrees C revealed higher stability of the Au/TNT-T catalyst, attributed to low sintering of gold nanoparticles. (C) 2016 Elsevier B.V. All rights reserved.