Mesoporous　metals　with　high　surface　area　hold　promise　for　a　variety　of　catalytic　applications,　especially　for　the　reduction　of　CO2　to　value-added　products.　This　study　has　used　a　novel　mesoporous　rhodium　(Rh)　nanoparticles,　which　were　recently　developed　via　a　simple　wet　chemical　reduction　approach　(Nat.　Commun.　2017,　8,　15581)　as　catalyst　for　CO2　methanation.　Highly　efficient　performance　and　selectivity　for　methane　formation　are　achieved　due　to　their　controllable　crystallinity,　high　porosity,　high　surface　energy,　and　large　number　of　atomic　steps　distributions.　The　mesoporous　Rh　nanoparticles,　possessing　the　largest　surface　area　(69　m(2)　g(-1)),　exhibit　a　substantially　higher　reaction　rate　(5.28　x　10(-5)　mol(CO2)　g(Rh)(-1)　s(-1))　than　the　nonporous　Rh　nanoparticles　(1.28　x　10(-5)　mol(CO2)　g(Rh)(-1)　s(-1)).　Our　results　indicate　the　extensive　use　of　mesoporous　metals　in　heterogeneous　catalysis　processes.