A range of Sr3P4O13:Ce 3+,Tb 3+ phosphors were prepared via a high temperature solid-state reaction method, and their phase compositions, particle morphologies, and luminescence properties were systematically studied by the X-ray diffractometry, scanning electron microscopy, and fluorescence spectroscopy. The results show that there is an overlap at 300-400 nm between the emission spectra of Sr3P4O13:Ce 3+ and excitation spectra of Sr3P4O13:Tb 3+. Under near-ultraviolet excitation (290 nm), the phosphors emit blue light (approximately 300-420 nm) for Ce 3+and yellow or green light (approximately 480-500 and 530-560 nm) for Tb 3+. When the mole fraction of Ce 3+is 0.08 and the mole fraction of Tb 3+ increases from 0.01 to 0.09, the 4f→5d electronic transition of Ce 3+ transfers energy to the 5D3 and 5D4 levels of Tb 3+, decreasing the luminescence intensity of Ce 3+ and gradually increasing the luminescence intensity of Tb 3+. This proves that Ce 3+→Tb 3+ energy transfer occurs in the Sr3P4O13 host. Therefore, the Ce 3+→Tb 3+ energy transfer mechanism is studied, and it is found that when the mole fraction of Tb 3+ is 0.09, the energy transfer efficiency reaches its highest value (86.46%). The corresponding color coordinates of Sr2.61P4O13:0.24Ce 3+,0.15Tb 3+ are in the green region; thus, Sr3P4O13∶Ce 3+,Tb 3+ co-doped phosphors are expected to be promising green fluorescent materials.