The　selective　catalytic　reduction　of　NOx　by　NH3　(NH3-SCR)　over　the　V2O5-WO3/TiO2　catalyst　is　the　state-of-the-art　technology　for　NOx　removal　from　both　stationary　and　mobile　sources.　Phosphorus　can　be　presented　in　the　fuel　gas　or　as　a　pelletizing　additive　to　increase　the　mechanical　strength　of　the　industrial　extruded　monolithic　V2O5-WO3/TiO2　catalyst.　Herein,　we　demonstrated　that　a　2-fold　increase　in　the　intrinsic　activity　without　detriments　to　N-2　selectivity　and　anti-H2O/SO2　stability　can　be　achieved　by　incorporating　V2O5WO3/TiO2　with　a　certain　amount　of　phosphorus,　which　was　generally　considered　as　an　inhibitor　for　such　type　of　catalyst.　Phosphorus　incorporation　enhanced　both　Bronsted　and　Lewis　acid　sites　on　V2O5WO3/TiO2,　and　NH3　bound　to　both　sites　are　involved　in　the　SCR　reaction　but　with　different　rates.　The　molecular　structure　of　surface　vanadyl　species　was　modulated　to　be　more　polymeric　(dimer　and　oligomer　content　increases　from　77%　to　90%)　by　phosphorus　incorporation　through　a　spatial　effect,　during　which　an　interaction　between　phosphorus　and　tungsten　was　observed.　This　study　reveals　the　promotional　effect　of　phosphorus　to　V2O5WO3/TiO2　catalyst,　which　is　important　for　the　fundamental　understanding　and　design　of　vanadium-based　catalyst.