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Tri-doped Ca9LiY2/3(PO4)7:Ce3+,Tb3+,Mn2+ phosphors were prepared by a high-temperature solid state method. Under UV light excitation, Ca9LiY2/3(PO4)7:Ce3+samples exhibit a broad band ranging from 320 to 500 nm. At 77 K, the emission spectra of Ca9LiY2/3(PO4)7:Ce3+samples present two obvious emission peaks, indicating that Ce3+ions occupy two different kinds of lattice sites (Ca(1/2) and Ca(3)). As a good sensitizer for Tb3+, Ce3+ions in Ca9LiY2/3(PO4)7 lattice can effectively transfer part of energy to Tb3+, and the energy transfer mechanism is determined to be dipole-dipole interaction. Consequently, the emitting color for Ce3+ and Tb3+ co-doped Ca9LiY2/3(PO4)7 samples can be tuned from bluish violet to green. In order to further enlarge the emission gamut, Mn2+ ions as red emission components were added, forming tri-doped single-phase Ca9LiY2/3(PO4)7:Ce3+,Tb3+,Mn2+ phosphors. The Ca9LiY2/3(PO4)7:Ce3+,Tb3+,Mn2+ phosphors exhibit tunable emission properties through controlling the relative doping concentration of Ce3+, Tb3+and Mn2+. Especially, Ca9LiY2/3(PO4)7:0.09Ce3+,0.12 Tb3+, 0.30Mn2+can emit warm white light. The sample shows good thermal stability. At 150 ℃, the emission intensity for Ce3+(360 nm), Tb3+ (545 nm) and Mn2+ (655 nm) decreases to 63%, 69%, and 72% of its initial intensity, respectively. Moreover, the sample obtains good stability after 10 cycles between room temperature and 150 ℃.