This　study　reports　Pt-decorated　ZnO　nanorod　arrays　(Pt/ZnO　NRs)　fabricated　by　low-cost　hydrothermal　and　sputtering　processes,　which　have　excellent　field　emission　(FE)　performance.　The　effects　of　the　Pt　thickness　on　the　morphology,　structure　and　FE　properties　of　ZnO　NRs　were　investigated.　It　was　found　that　highly　oriented　ZnO　NRs　with　sharp　tips　were　grown　on　a　Zn　substrate　and　the　surface　of　ZnO　NRs　were　uniformly　covered　with　Pt　nanoparticles　(NPs)　with　a　diameter　of　around　2-3　nm.　The　FE　properties　of　ZnO　NRs　were　greatly　improved　by　optimizing　the　amount　of　Pt　NPs.　The　results　found　that　the　ZnO　NR　emitters　coated　with　Pt　NPs　of　15　nm　thickness　(Pt15/ZnO　NRs)　exhibited　the　best　FE　characteristics,　which　have　the　lowest　turn-on　field　at　1.45　V　μm-1　and　the　highest　field　enhancement　factor　of　around　5405.　More　importantly,　the　maximum　emission　current　density　of　as-fabricated　Pt15/ZnO　NR　emitters　was　about　1900　times　that　of　the　bare　ZnO　emitters.　The　Pt　coating　not　only　improves　electron　conduction　and　heat　dissipation　of　the　emitters　but　also　balances　the　emission　point　density　and　the　screening　effect.　©　The　Royal　Society　of　Chemistry.