The　selective　catalytic　hydrogenation　of　styrene-butadiene-styrene　block　copolymer　(SBS)　is　to　selectively　hydrogenate　the　unsaturated　C　C　in　polybutadiene　segment　while　maintaining　the　phenyl　group　in　polystyrene　segment　intact　so　as　to　yield　high-valued　hydrogenated　products　SEBS　with　greatly　improved　performance.　In　order　to　eliminate　the　diffusion　limitation,　herein,　three-dimensional　ordered　super-macroporous　carbon　nitride　(3DOM　g-C3N4)　was　successfully　synthesized　via　thermal　condensation　of　cyanamide　with　colloidal　SiO2sub-microspheres　as　the　template.　Afterwards,　the　Pd/3DOM　g-C3N4　catalyst　was　obtained　by　chemical　reduction　method　and　applied　for　selective　catalytic　hydrogenation　of　SBS.　The　results　showed　that　the　Pd/3DOM　g-C3N4　catalyst　possessed　a　three-dimensional　penetrating　structure　of　super-macroporous-macroporous-mesoporous　multistage　pore　with　the　small-sized　and　well-dispersed　Pd　nanoparticles　over　it.　Such　catalyst　exhibited　excellent　hydrogenation　activity　and　selectivity　under　mild　reaction　conditions.　According　to　the　Fourier　transform　infrared　(FTIR)　characterization,　the　total　hydrogenation　degree　of　1,2-C　C　and　1,4-C　C　to　SBS　was　98%,　while　the　benzene　ring　was　not　hydrogenated　thus　the　selectivity　to　C　C　was　100%.　The　excellent　catalytic　performance　is　mainly　attributed　to　the　unique　three-dimensional　penetrating　structure　of　super-macroporous-macroporous-mesoporous　multistage　pore　of　the　support,　which　can　effectively　eliminate　the　macromolecules　diffusion　limitation　in　pores,　thereby　greatly　improving　the　accessibility　to　the　active　sites.　The　strong　interaction　between　Pd　and　pyridinic　N　in　the　g-C3N4support　is　beneficial　to　anchoring　Pd2+　during　impregnation　process,　and　then　obtains　Pd　nanoparticles　with　small　particle　size　and　high　dispersion　and　stability.　©　2023　Chemical　Industry　Press.　All　rights　reserved.