The tunable spectroscopy properties of Eu3+-activated Ba2Gd2Si4O13 phosphors under different wavelengths from vacuum ultraviolet (VUV) to ultraviolet region have been demonstrated. From the emission spectra, a broad band centered at 410 nm can be observed by choosing the suitable excitation wavelength, which is determined to be the defects produced under high temperature. Based on the result, the phosphor shows a tunable emission depending on the excitation source and the concentration of Eu3+. In addition, the VUV photoluminescence property of a series of Ba2Gd2Si4O13:Eu3+ indicates that the optimal sample is Ba2Gd1.9Si4O13:5 %Eu3+ whose emitting color and decay time is beneficial for the application compared to the value for the commercial red-emitting phosphor.