A series of novel single-phase Ca₉NaZn(PO₄)₇:Ce³⁺,Tb³⁺ phosph ors are synthesized by a high temperature solid-state reaction method and the luminescence and energy transfer properties of the samples are studied in details.When excited by 310nm,the Ce³⁺ and Tb³⁺ co-doped phosphor exhibits two emission parts,which are ascribed to ^5d→^4f and ⁵D₄→⁷F_3,4,5,6 transitions of Ce³⁺ and Tb³⁺,respectively.The results show that the energy transfer process between Ce³⁺ and Tb³⁺ belongs to a resonant type,th e critical distance is calculated to be 1.216nm,and the energy transfer mechani s m is proved to be a quadrupole-quadrupole interaction.Ultimately, by utilizing the principle of energy transfer and appropriately tuning Ce 3+ and Tb³⁺ concentrations,Ca₉NaZn(PO₄)₇:0.02Ce³⁺, yTb³⁺ can realize tunable emission color from the viol et-blue to green region and have potential applications as a UV-convertible phosphor in white light-emitting d iodes.