Abstract: A series of Na₂Ca_3-xSi₆O₁₆:xEu³⁺ was prepared with high temperature solid-state reaction and structurally characterized with X-ray powder diffraction. The results of X-ray powder diffraction showed that Eu³⁺-doping had no significant effect on the crystal structure of Na₂Ca₃Si₆O₁₆:Eu³⁺. Its optical properties were checked with the spectrofluorometer. The results showed that the Na₂Ca_3-xSi₆O₁₆:xEu³⁺ phosphor emitted red light with the strongest emission peak at 611 nm. The doping of Eu³⁺ did not change the peak shape and position of the emission spectra of Na₂Ca_3-xSi₆O₁₆:xEu³⁺phosphor. However, the doping content (mole fraction) of Eu³⁺ was related to the luminescence intensity. When the concentration of Eu³⁺ was 0.08, the Na₂Ca_3-xSi₆O₁₆:xEu³⁺ showed the strongest luminescence intensity. The concentration quenching was observed when Eu³⁺ concentration was over 0.08, and the concentration quenching mechanism was verified as multipole-multipole interaction. The results indicated that Na₂Ca_2.92Si₆O₁₆:0.08Eu³⁺ phosphor was a potential red light-emitting material for white LED.