Binary　Cr-Mo　oxide　catalysts　(denoted　as　Cr(x)Mo(y),　x/y　=　nominal　Cr/Mo　molar　ratio)　supported　on　MgO-coated　polyhedral　three-dimensional　(3D)　mesoporous　SBA-16　(MS)　were　fabricated　for　the　oxidative　dehydrogenation　of　iso-butane.　The　materials　were　characterized　by　a　number　of　techniques　for　the　establishment　of　the　relationships　between　physicochemical　properties　and　catalytic　performance.　The　use　of　high-surface-area　3D　MS　as　support　for　Cr-Mo　oxide　catalysts　leads　to　increases　of　catalytic　activity　and　of　selectivity　to　iso-butene.　The　Cr(x)Mo(y)　catalysts　show　higher　isobutene　yield　than　the　Cr/MS　or　Mo/MS　catalyst.　Under　the　conditions　of　iso-butane/O-2　molar　ratio　=　1/2,　space　velocity　=　30,000　mL/(gh),　and　reaction　temperature　=　540　degrees　C,　maximal　iso-butene　yield　of　7.5%　(iso-butane　conversion　=　10.0%　and　iso-butene　selectivity　=　75.0%)　can　be　achieved　over　the　Cr3Mo1　catalyst.　Based　on　the　results　of　characterization　and　activity　evaluation,　we　conclude　that　the　excellent　catalytic　performance　can　be　attributed　to　the　moderate　basicity,　good　dispersion　of　CrOx　and　MoOx　high　Cr6+　content,　and　high　initial　H-2　consumption　rate　of　Cr3Mo1.　(C)　2008　Elsevier　B.V.　All　rights　reserved.