The sol-gel route is used to prepare samarium (Sm⁺³) ions doped in silica monoliths as a function of active ion concentrations up to 0.0178%. The spectroscopic activity of Sm⁺³ ions doped-silica matrices is investigated using UV- Visible spectroscopy and photoluminescence spectroscopy. ⁴G_5/2 emissions are observed from a minority of isolated Sm⁺³ ions within the pores structure of silica matrix, UV-Vis spectra reveals absorption peaks due to Sm⁺³ active centers. X-ray diffraction and FTIR results support the distribution of such ions in these porous. Analysis indicates that at high doping levels, most ions reside in clusters and ⁴G_5/2 emission, which is demonstrated by the quenching processes observed in the corresponding spectra. Some spectroscopic parameters such as emission cross-section and oscillator strength are determined and analyzed.