A　series　of　NdV/Ti-x%　catalysts　were　prepared　by　a　microwave-assisted　deposition-precipitation　method,　and　their　catalytic　performance　for　the　selective　catalytic　reduction　(SCR)　of　NO　by　NH3　was　investigated.　Impressively,　the　SCR　activity　of　the　obtained　catalyst　was　markedly　influenced　by　the　amount　of　vanadate　added.　The　results　show　that　the　NdV/Ti-x%　catalysts　not　only　possess　good　low-temperature　catalyst　activities　but　also　exhibit　excellent　SO2　resistance　performances　in　the　presence　of　300　ppm　SO2　and/or　10　vol　%　H2O.　Furthermore,　SO2　promotes　the　activity　of　the　NdV/Ti-10%　catalyst.　These　catalysts　were　characterized　using　X-ray　diffraction　(XRD),　H2　temperature-programmed　reduction　(H2-TPR),　NH3　temperature-programmed　desorption　(NH3-TPD),　scanning　electron　microscopy　(SEM),　transmission　electron　microscopy　(TEM),　X-ray　photoelectron　spectroscopy　(XPS),　in　situ　diffuse　reflectance　Fourier　transforms　(DRIFTs),　etc.　The　in　situ　DRIFT　results　indicate　that　the　NH3-SCR　reaction　over　the　well-dispersed　vanadate　catalyst　follows　the　Eley-Rideal　(E-R)　and　Langmuir-Hinshelwood　(L-H)　mechanisms.　In　particular,　the　SCR　reaction　following　the　E-R　mechanism　is　rapid　and　significantly　improves　SO2　tolerance.　In　addition,　the　SO2　adsorption　could　be　restrained　on　the　NdV/Ti-10%　catalyst,　which　effectively　restrained　the　deposition　of　sulfate　species　and　endowed　catalysts　with　strong　SO2　tolerance.　Meanwhile,　the　effective　suppression　of　SO2　adsorption　allowed　the　NdV/Ti-10%　catalyst　to　maintain　Eley-Rideal　(E-R)　pathways.　This　work　paves　the　way　for　the　development　of　high-performance　SO2-tolerant　SCR　catalysts.　　©　2023　American　Chemical　Society.