Novel blue-green emitting Ce3+- and Tb3+-activated K2CaP2O7 (KCPO) luminescent materials were synthesized via a solid-state reaction method. X-ray diffraction, luminescence spectroscopy, decay time, and fluorescent thermal stability tests have been used to characterize the prepared samples. The KCPO:Ce3+,Tb3+ luminescence spectra show broad band of Ce3+ ions and characteristic line of Tb3+ ion transition (D-5(4)-F-7(5)). The color variation in the light emitting from blue to green under UV excitation can be obtained by tailoring the Tb3+ content in KCPO:Ce3+. Besides, Ce3+ ions obviously intensify Tb3+ ion emission through an effective energy transfer process, which was confirmed from decay curves. The energy transfer efficiency was determined to be 82.51%. A resonant type mechanism via the dipole-quadrupole interaction can be proposed for energy transfer. As a whole, the KCPO:Ce3+,Tb3+ phosphor exhibits excellent performance in the range from 77 to 673 K, indicating the phosphors are highly potential candidates for solid-state lighting.