Compared with conventional destructive mechanoluminescent materials, trap-controlled mechanoluminescent materials generally preserve high structural integrity and repeatability during the mechanoluminescent process. The trap-controlled mechanoluminescent materials have attracted recent attention in diverse fields of stress sensors, mechano-driven lighting and displays. The development of high-performance trap-controlled mechanoluminescent materials is of great significance to promote the application of mechanoluminescence. This paper was to investigate a trap-controlled reproducible mechanoluminescent material, i.e., Ca2Ga2GeO7:Pr3+, and analyze its luminescent properties by the measurements of X-ray diffraction patterns, diffuse reflection spectra, phosphorescent decay curves, photoluminescence, mechanoluminescence and thermoluminescence. The emission peaks of photoluminescence and mechanoluminescenc are the same at 488 nm, 610 nm and 648 nm, corresponding to the energy level transition of Pr3+ of 3H4→3P0, 3H4→1D2 and 3F2→3P0, respectively. A slow-decaying mechanoluminescent behavior occurs when the continuous frictional stimulation and the mechanoluminescent intensity increase linearly with increasing the pressure. According to the thermoluminescent measurement, the slow-decaying mechanoluminescence is attributed to existence of deep traps. The deep traps provide an electron replenishment for shallow traps for Ca2Ga2GeO7:Pr3+ under continuous stress stimulation. This paper may provide a material-and-experimental basis for the development and application of high-performance trap-controlled mechanoluminescent materials.