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Sm3+-activated Ca2SiO4 red phosphors were prepared by the conventional high-temperature solid-state reaction method,and the effects of sodium (Na+) and samarium (Sm3+) ions doping concentrations on their crystal structure and luminescent properties were investigated by X-ray diffraction (XRD) and fluorescent spectrofluorometer.XRD patterns demonstrate that a well-crystalline structure forms in the phosphors when they are treated by calcination at 1200℃ for 4 h,and the excitation spectra exhibit good absorption in the range between 350 and 420 nm.Under the irradiation of 405 nm near-ultraviolet (NUV) light,the spectra of the phosphors show a main emission peak at 601 nm attributed to the 4G5/2→6H7/2 transition of Sm3+ ions,and its intensity is greatly influenced by the concentrations of Sm3+ and Na2CO3.When the concentrations of Sm3+ ions and Na2CO3 are 2mo1％ and 6mo1％,respectively,the optimal emission intensity can be obtained.From strong absorption in the near ultraviolet zone,the Na0.06Sm0.02Ca1.92SiO4 phosphor is a promising red-emitting phosphor for white light emitting diodes (W-LEDs).