Developing　phosphors　with　narrow　band　emission　and　excellent　performance　is　the　main　goal　of　current　leading　research.　In　this　study,　a　novel　narrow　band　blue-emitting　phosphor　Rb2ZrSi3O9:　Eu2+　was　prepared　that　can　be　fully　excited　by　near　ultraviolet　(NUV)　light,　emits　a　bright　blue　light　peak　at　470　nm,　and　has　a　full　width　at　half　maximum　(FWHM)　of　60　nm.　The　synthesized　Rb2ZrSi3O9:　Eu2+　had　excellent　photoluminescence　properties　that　were　reflected　in　its　good　thermal　stability　(up　to　82%)　and　high　internal　quantum　efficiency　(up　to　75%).　These　remarkable　luminescence　properties　were　mainly　ascribed　to　the　highly　symmetric　and　dense　crystal　structure　composed　of　[Si3O9](6-)　ring　pairs.　Multiple　emission　centers　in　the　Rb2ZrSi3O9:　Eu2+　phosphor　were　confirmed　through　the　photoluminescence　(PL)　spectra　and　time-resolved　(PL)　spectra.　A　bright　warm　WLED　device　with　a　low　correlated　color　temperature　(3386　K)　and　high　color-rendering　index　(CRI　similar　to　89.3)　was　produced　by　combining　the　blue　phosphor　with　(Sr,　Ba)(2)SiO4:　Eu2+　and　CaAlSiN3:　Eu2+　and　NUV　(380　nm).　The　results　indicate　that　Rb2ZrSi3O9:　Eu2+　could　be　a　promising　phosphor　for　use　in　WLEDs.