Na1-xEuxTbMo2O8 nanoparticles were prepared by a hydrothermal method.X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and photoluminescence(PL)spectra were used to characterize the structures,morphologies and the luminescent properties of as-prepared products.Emission and excitation spectra showed that the phosphor exhibits a dominant red emission at 612 nm with excitation wavelength of 465 nm at room temperature.The optimized concentration of Eu3+ is 5 mol.%for the highest emission intensity at 612 nm.The concentration quenching mechanism can be interpreted by the nearest-neighbor ions interaction of Eu3+ ions.It is found that Eu3+ concentration has great impact on the luminescent intensity which is attributed to the variation of the local symmetry.The red emission is visible to naked eyes,indicating that NaTbMo2O8 may act as a promising host material for Eu3+ doped red phosphors.