Direct　methanol　fuel　cells　(DMFCs)　face　commercialization　challenges　due　to　sluggish　methanol　oxidation　reaction　(MOR)　and　catalyst　poisoning.　Pd-based　alloy　catalysts　show　promise　in　alkaline　media,　but　their　high　cost,　poor　stability,　and　CO　intermediate　toxicity　hinder　practical　applications.　Herein,　we　present　a　melamine-assisted　confinement　strategy　to　construct　ultra-small　PdZn　ordered　intermetallic　nanoparticles　(O-PdZn@MEL/C)　with　optimized　electronic　configurations.　The　carbon　shell　derived　from　pyrolyzed　melamine　imposes　spatial　constraints　that　suppress　nanoparticle　coalescence　while　enhancing　structural　stability.　Zn　incorporation　induces　d-orbital　hybridization,　which　downshifts　the　Pd　d-band　center　to　weaken　CO*　adsorption　while　strengthening　OH*　binding　at　Zn　sites.　The　catalyst　demonstrates　exceptional　mass　activity　(2505.35　mA·mgPd　−1　),　3.65　times　higher　than　that　of　commercial　Pd/C,　with　a　lower　onset　potential　(0.47　V　vs.　reversible　hydrogen　electrode　(RHE)).　Stability　tests　reveal　94.3%　activity　retention　after　500　cyclic　voltammetry　(CV)　cycles　and　only　52.5%　current　density　decay　during　4000　s　operation.　This　work　establishes　d-band　engineering　through　ordered　intermetallic　design　as　an　effective　pathway　to　develop　CO-tolerant,　high-performance　anode　catalysts　for　advanced　fuel　cells.　©　The　Author(s)　2025.　Published　by　Tsinghua　University　Press.