Nitric　oxide　(NO),　as　a　vital　signaling　molecule　related　to　different　physiological　and　pathological　processes　in　living　systems,　is　closely　associated　with　cancer　and　cardiovascular　disease.　However,　the　detection　of　NO　in　real-time　remains　a　difficulty.　Here,　PtBi　alloy　nanoparticles　(NPs)　were　synthesized,　dealloyed,　and　then　fabricated　to　NP-based　electrodes　for　the　electrochemical　detection　of　NO.　Transmission　electron　microscopy　(TEM),　small-angle　X-ray　scattering　(SAXS),　and　nitrogen　physical　adsorption/desorption　show　that　dealloyed　PtBi　alloy　nanoparticles　(dPtBi　NPs)　have　a　porous　nanostructure.　Electrochemical　impedance　spectroscopy　and　cyclic　voltammetry　results　exhibit　that　the　dPtBi　NP　electrode　possesses　unique　electrocatalytic　features　such　as　low　charge　transfer　resistance　and　large　electrochemically　active　surface　area,　which　lead　to　its　excellent　NO　electrochemical　sensing　performance.　Owing　to　the　higher　density　of　catalytical　active　sites　formed　PtBi　bimetallic　interface,　the　dPtBi　NP　electrode　displays　superior　electrocatalytic　activity　toward　the　oxidation　of　NO　with　a　peak　potential　at　0.74　V　vs.　SCE.　The　dPtBi　NP　electrode　shows　a　wide　dynamic　range　(0.09-31.5　mu　M)　and　a　low　detection　limit　of　1　nM　(3s/k)　as　well　as　high　sensitivity　(130　and　36.5　mu　A　mu　M-1　cm(-2)).　Moreover,　the　developed　dPtBi　NP-based　electrochemical　sensor　also　exhibited　good　reproducibility　(RSD　5.7%)　and　repeatability　(RSD　3.4%).　The　electrochemical　sensor　was　successfully　used　for　the　sensitive　detection　of　NO　produced　by　live　cells.　This　study　indicates　a　highly　effective　approach　for　regulating　the　composition　and　nanostructures　of　metal　alloy　nanomaterials,　which　might　provide　new　technical　insights　for　developing　high-performance　NO-sensitive　systems,　and　have　important　implications　in　enabling　real-time　detection　of　NO　produced　by　live　cells.