Shape-specific　CeO2　nanocrystals　(rods,　cubes,　spheres　and　nanoparticles)　with　well-defined　crystal　facets　and　hierarchically　porous　structure　were　successfully　synthesized　and　used　as　model　catalysts　to　study　the　structure-dependent　behavior　and　reaction　mechanism　for　H2S　selective　oxidation　over　ceria-based　catalysts.　It　is　deduced　that　the　defect　sites　and　base　properties　of　CeO2　are　intrinsically　determined　by　the　surface　crystal　facets.　Among　the　nanocrystals,　CeO2　nanorods　with　well-defined　{110}　and　{100}　crystal　facets　exhibits　superb　catalytic　activity　and　sulfur　selectivity.　The　high　reactivity　for　H2S　selective　oxidation　is　attributed　to　the　high　concentration　of　surface　oxygen　vacancies　which　are　beneficial　for　the　conversion　of　lattice　oxygen　to　active　oxygen　species.　Besides,　the　presence　of　hierarchically　porous　structure　of　CeO2　nanorods　hinders　the　formation　of　SO2　and　sulfate,　ensuring　good　sulfur　selectivity　and　catalyst　stability.　Through　a　combined　approach　of　density-functional　theory　(DFT)　calculations　and　in　situ　DRIFTS　investigation,　the　plausible　reaction　mechanism　and　nature　of　active　sites　for　H2S　selective　oxidation　over　CeO2　catalysts　have　been　revealed.