H2　recycling　between　naphthalene,　tetralin　and　decalin　can　be　a　promising　application　in　chemical　hydrogen　storage,　which　is　an　important　area　for　hydrogen　fuel　cell　applications.　Pt-based　catalysts　can　be　used　in　the　dehydrogenation　reaction　for　this　purpose　and　support　modification　can　effectively　improve　the　catalytic　performance.　Effects　of　preparation　method,　Mg/Al　molar　ratio　and　metal　composition　on　the　Pt-based　LDH-derived　nanoplatelets　catalysts　for　decalin　dehydrogenation　were　systematically　investigated　in　this　work.　The　results　out　of　this　study　indicated　that　the　preparation　method,　Mg/Al　molar　ratio　and　metal　composition　exert　significant　effects　on　the　microstructure　and　catalytic　performance　of　the　catalysts　for　decalin　dehydrogenation.　The　Pt/MgAl-LDO　catalyst　with　a　Mg/Al　molar　ratio　of　4　prepared　by　hydrothermal　method　yielded　the　largest　specific　surface　area　of　374　m2/g　and　the　smallest　average　Pt　particle　size　of　1.62　nm,　which　exhibited　excellent　H2　production　yield　of　5.94　mol/gPt.　These　are　mainly　attributed　to　the　sheet-like　structure,　large　specific　surface　area　and　strong　Pt-support　interaction,　leading　to　the　superior　Pt　dispersion.　This　work　provides　a　new　approach　for　the　preparation　of　low-cost　and　high-performance　decalin　dehydrogenation　catalysts,　which　is　of　great　significance　for　the　application　of　liquid-phase　organic　hydride　hydrogen　storage　technology.