A series of novel red-emitting Sm3+-doped phosphors were synthesized by a conventional solid state reaction. The crystal structure and atomic coordinates of was characterized by Rietveld refinement. Luminesce properties of as-synthesized Sm3+-doped phosphors are carried out by PL/PLE, decay life time, thermal quenching as well as reflectance spectrometer and LED fabrications. The results indicate that composition-optimized phosphor exhibits orange-red emission peaks located on 564, 601, 608 and 648 nm attributed to the transitions of 4G5/2 → 6H5/2, 4G5/2 → 6H7/2, 4G5/2 →6H7/2 and 4G5/2 → 6H9/2, respectively. The results of LED fabrication by combing 380 chip and blue/green phosphors are demonstrated in this study. Finally, from viewpoint of theoretical calculations, band structure and density of state for host and Sm3+-doped phosphor are studied by first principles calculations. All the results indicate that our phosphors could be a potential material for white light-emitting diodes. FIG. 1 (a) Electroluminescence spectrum of BaMgAl10O17:Eu2+, Ba2SiO4:Eu2+ and as-synthesized red phosphor with 380 chip. Inset: photo image of LED device derived at 20 mA; (b) CIE coordinates of red phosphor excited at 365 nm. Inset: red phosphor image in UV box under 365 nm excitation.