The　nano-sized　polycrystalline　Ce0.6Zr0.3Y0.1O2　(CZY)　support　was　fabricated　adopting　the　cetyltrimethyl　ammonium　bromide　(CrAB)-assisted　hydrothermal　treatment　method　and　the　CZY-supported　nanosized　gold　catalysts,　y%　AuOx/CZY　(y%　represents　the　Au　weight　percentage.　y　=　0.2-10.0),　were　prepared　using　an　in　situ　reduction　procedure　with　HAuCl4　as　Au　source,　NaBH4　as　reducing　agent,　and　poly(N-vinyl-2-pyrrolidone)　(PVP)　as　surfactant.　We　characterized　the　physicochemical　properties　of　these　materials　by　means　of　the　XRD,　Brunauer-Emmett-Teller　(BET),　high-resolution　scanning　electron　microscopic　(HRSEM),　high-resolution　transmission　electron　microscopic　(HRTEM)/selected　area　electron　diffraction　(SAED),　XPS,　and　hydrogen　temperature-programmed　reduction　(H-2-TPR)　techniques,　and　examined　their　catalytic　activities　for　the　combustion　of　methane.　It　is　observed　that　the　CZY　and　gold　were　nanoparticles　with　the　diameter　of　5-50　and　2-20　nm,　respectively.　At　a　lower　gold　loading　(y　＜=　0.6),　the　gold　mainly　existed　in　a　highly　dispersed　AuOx　(Au3+)　domain　on　the　CZY　surfaces;　at　a　higher　gold　loading　(y　＞=　1.0),　the　gold　were　present　in　the　form　of　metallic　AuO　cluster　as　well　as　dispersed　AuO,　domains.　With　the　introduction　of　gold,　the　reducibility　of　the　y%　AuOx/CZY　catalysts　was　improved　significantly,　possibly　due　to　the　synergistic　action　between　the　nano-sized　gold　and　the　nanocrystalline　CZY.　Among　the　y%　AuOx/CZY　catalysts,　the　one　at　y　=　0.2　showed　the　best　activity　for　methane　combustion.　It　is　suggested　that　the　good　catalytic　performance　of　CZY-supported　gold　materials　with　a　lower　gold　loading　(＜1.0%)　is　associated　with　the　high　dispersion　of　AuOx　domains,　high　atomic　ratio　of　Au3+/Au-0,　nano-sized　Au　and　CZY　particles,　and　good　reducibility.　(C)　2008　Elsevier　B.V.　All　rights　reserved.