In this study, an efficient mechanoluminescent material, namely Y3GaO6:Tb3+, with green emission was prepared by high-temperature solid-phase synthesis. X-ray diffraction (XRD) shows that the sample belongs to the orthorhombic crystal system with the space group Cmc21. The luminescence intensity of the materials is related to the content of the luminescent centers, and both photoluminescence (PL) and mechanoluminescence (ML) show that the optimum doping level of Tb3+ is 0.07. In both tensile and frictional applications, the ML intensity is linearly correlated with the magnitude of applied stress. Analysis of the thermoluminescence (TL) spectra indicates that the ML of the material arises from carriers released from the trap under stress stimulation, thus revealing its mechanism of ML property. Finally, the study demonstrates the mechanoluminescene pattern of Y3GaO6:Tb3+.