KBaPO4∶Eu3+ phosphor was synthesized by the high temperature solid state reaction method, and the effects of Eu3+ concentration and charge compensators on the luminescent characteristics of the phosphor were investigated. The phase present of the samples was characterized by powder Xray diffraction (XRD) (D/maxrA, Cu Kα, 40 kV, 40 mA, λ=0.15406 nm). The excitation and emission spectra of these phosphors were measured by a SHIMADZU RF540 fluorescence spectrophotometer. The research results show that under 400 nm excitation, the phosphor presents several emission peaks, which correspond to the 5D0→7FJ(J=0,1,2,3,4) transition of Eu3+, respectively, and the highest emission locate at 621 nm; monitored at 621 nm emission, the excitation spectrum contains 200~350 nm and 350~450 nm two excitation bands, which correspond to a weak charge transition broad band absorption CTS and a strong ff transition absorption of Eu3+, respectively, and the highest peak locates at 400 nm; the emission intensity of the phosphor was influenced by the Eu3+ concentration, and it reaches the maximum at 5 mol% Eu3+; the concentration quenching occurs when the Eu3+ concentration is beyond 5 mol%, and the concentration selfquenching mechanisms are the dd interaction by Dexter theory; under the conditions of charge compensator incorporated in the phosphor, the emission intensity can be enhanced, and can obtain the prime function with doping Li+ or Cl.