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Color tuning and luminescence enhancement are predominant challenges for improving the perfor-mance of white light emitting diodes (LEDs) toward commercial application. In this paper, a novel promising Ba2?xCaxSiO4?yN2/3y:Eu2t phosphors with tunable and enhanced luminescence for phos-phors converted LEDs (pc-LEDs) have been successfully synthesized by a direct gas-reduction nitridation method. The effects of Ca and N doping on the phase purity, morphology and optical properties of Ba2?xCaxSiO4?yN2/3y:Eu2t phosphors were also systematically investigated. The optical results show that Ba2?xCaxSiO4?yN2/3y:Eu2t phosphors can be actively excited over a broad range from 250 to 430 nm. With the adding of different concentrations of Ca2 t ions in phosphors, the emission color wavelength can be tailored from 501 to 441 nm by a 375 nm NUV LED excitation source. Furthermore, it has been found that the emission and absorption of Ba2 ? xCaxSiO4:Eu2 t phosphor can be significantly improved when N3? ions were introduced into the host lattices. The intensity of Ba1.5Ca0.5SiO4?yN2/3y:Eu2 t phosphor was 3.4 times higher than the phosphor without N doping. The fabrication and char-acterization of pc-LEDs using Ba2?xCaxSiO4?yN2/3y:Eu2t phosphors-silica gel as the coating layer onto 375 nm-emitting InGaN LED caps demonstrated the superior optical and current tolerant properties, making it a promising and competitive candidate for commercial utilization in white LED applications.