Eu3+-doped Gd2Mo3O9 was prepared by solid-state reaction method using Na2CO3 as flux and characterized by powder X-ray diffractometry. According to X-ray diffraction, this material belonged to a tetragonal system with space group I41/a. The effects of flux content and sintering temperature on the luminescent properties were investigated with the emission and excitation spectra. The results showed that flux content and sintering temperature had effects on the luminescent properties, the optimized flux content and the best temperature was 3% and 800 ℃, respectively. The excitation and emission spectra also showed that this phosphor could be effectively excited by C-T band (280 nm), ultraviolet light 395 nm and blue light 465 nm. The wavelengths at 395 and 465 nm were nicely fitting in with the widely applied output wavelengths of ultraviolet or blue LED chips. Integrated emission intensity of Gd2Mo3O9∶Eu was twice higher than that of Y2O2S∶Eu3+ under 395 nm excitation. The Eu3+ doped Gd2Mo3O9 phosphor may be a better candidate in solid-state lighting applications.