Abstract: The red phosphor BaMg₂（PO₄）2 :Sm³⁺ was synthesized by high temperature solid state reaction and its luminescent properties were also investigated.It show three major emission peeks locating at 564 nm,600 nm,648 nm,corresponding to the ⁴G_5/2→⁶H_5/2、⁴G_5/2→⁶H_7/2、⁴G_5/2→⁶H_9/2 typical transitions of Sm³⁺ respectively,and the strongest peak appears at 600 nm.The influence of the Sm³⁺ concentration to the emission intensity was investigated and the concentration quench was happened when the concentration of Sm³⁺ ions was 0.01.The role of charge compensation of Li⁺,Na⁺,K⁺,F^- and Cl^- ions can all increased the luminescent intensity of BaMg₂（PO₄）2:Sm³⁺,K⁺ ions gave the best improvement to enhance the intensity of the emission obviously.K+ ion is the optimal charge compensation.BaMg₂（PO₄）2:Sm³⁺ is a potential application of white-light LED red phosphors.