Spin　engineering　provides　a　powerful　strategy　for　manipulating　the　interaction　between　electrons　in　the　d　orbital　and　oxygen-containing　adsorbates,　while　a　little　endeavor　was　performed　to　understand　whether　such　a　strategy　can　make　a　prosperous　enhancement　for　fuel　electrooxidations.　Herein,　we　demonstrate　that　spin　engineering　of　trimetallic　Pd-Fe-Pt　nanomeshes　(NMs)　can　achieve　superior　enhancement　for　fuel　electrooxidations.　Magnetization　characterizations　reveal　that　Pd59Fe27Pt14　NMs　own　the　highest　number　of　polarized　spins　(mu(b)　=　0.85　mu　B/f.u.),　playing　an　important　role　on　facilitating　the　adsorption　of　OHads　to　promote　the　oxidation　of　COads,　as　confirmed　by　theoretical　results.　Consequently,　the　optimized　Pd59Fe27Pt14　NMs　exhibit　excellent　methanol　oxidation　reaction　activity　and　stability　with　a　mass　activity　of　1.61　A　mg(Pt)(-1),　2.6-fold　and　7.3-fold　larger　than　those　of　PtRu/C　and　Pt/C.　Such　catalysts　also　present　exceptional　performances　in　ethanol　oxidation　and　formic　acid　oxidation　reactions.　Our　work　highlights　a　new　strategy　for　designing　efficient　electrocatalysts　for　fuel　electrooxidations　and　beyond.