Vanadium　doped,　nitrogen　doped,　and　vanadium　and　nitrogen　co-doped　SrTiO3　powders　with　size　of　20-30　nm　in　diameter　were　prepared　by　high　energy　milling　method　respectively.　It　was　found　that　compared　with　those　of　pure　SrTiO3,　the　photocatalytic　activities　of　these　three　doped　SrTiO3　samples　for　decomposing　NO　under　visible　light　(λ＞400　nm)　and　near　ultraviolet　light　(λ＞290　nm)　irradiation　were　improved,　and　the　co-doped　sample　exhibited　the　highest　photocatalytic　activity.　43.2%　NO　could　be　eliminated　under　the　irradiation　of　light　with　wavelength　larger　than　400nm,　about　3　times　higher　than　that　by　pure　SrTiO　3.　The　photocatalytic　activity　of　this　sample　near　ultraviolet　range　is　about　1.7　times　higher　than　that　of　pure　SrTiO3.　The　high　visible　light　photocatalytic　activity　of　this　substance　may　be　due　to　the　high　visible　light　absorption　and　large　specific　surface　area.　©　(2009)　Trans　Tech　Publications.