The fluorescence properties of Sm3+and Sm2+ions incorporated in silicate glasses were measured using steady-state and laser-induced line narrowing techniques and the effect of Al3+ions to the local structure around the Sm2+ion was investigated. Sm3+ion-containing glasses prepared by a sol–gel method were reacted with H2gas to form the Sm2+ions. The energies of the three Stark levels of the5D0→7F1transition were analyzed usingC2vsymmetry. The addition of Al3+ions facilitates dispersion of the Sm2+ions and increases the coordination number of the Sm2+ion due to the long distance between the Sm2+and O2−ions, resulting in the increased fluorescence intensity. The fluorescence intensity of the Sm2+and Sm3+ions considerably increases in glasses containing more than 5 mol &percent; Al2O3. ©1997 American Institute of Physics.