Colorless and transparent Li6Gd(BO3)3:Ce crystals are grown with the Czoralski method. Their optical characteristics and luminescence processes are also investigated. The ultraviolet-vaccum ultraviolet (UV-VUV) transmittance spectra are measured and the result shows that absorption peaks due to Ce3+ ions and Gd3+ ions, and the absorption band related to charge transfer band of Ce4+ ions are present. According to the UV-VUV excitation and emission spectra, it is found that there appear luminescences of 5d4f radiative transitions of Ce3+ ions and of 4f4f radiative transitions of Gd3+ ions, and also Gd3+Ce3+ energy transfer. The X-ray and -ray stimulated luminescence spectra show that the scintillation light of the crystal is mainly from Ce3+ ions.