Novel green nanophosphors Ca2Gd2W3O14: Tb3+ were synthesized by solid state reaction method. From the X-ray diffraction profiles it is observed that Tb3+: Ca2Gd2W3O14 phosphors were crystallized in the form of tetragonal structure. The scanning electron microscopy (SEM) image shows that the particle size is at around 300 nm. In addition to these the prepared powder phosphors were also examined by the energy dispersive X-ray analysis (EDAX), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL) and mechanoluminescence (ML) spectra. Emission spectra of Tb3+: Ca2Gd2W3O14 nanophosphors have shown bright green emission at 545 nm (D-5(4) -> F-7(5)) with an excitation wavelength lambda(exci) = 374 nm (F-7(6) -> (5)G(6)). ML spectra shows the radiation effect on the Ca2Gd2W3O14: Tb3+ nanophosphors and from that it was observed that these phosphors are very less sensitive for lower exposure.