Oxyorthosilicate Lu 2SiO 5:Ce and pyrosilicate Lu 2Si 2O 7:Ce are known as effective scintillators. The intrinsic luminescence of Lu 2Si 2O 7:Ce crystals at 4,5-6,0 eV was discovered. The origin of this emission is explained in terms of crystallographic peculiarities and specificity of recombination processes in crystals.