Abstract: The paper deals with the spectroscopic studies of sol-gel systems doped with rare-earth ions and co-doped with chromium. Doped samples of Nd3+: Cr3+ silica zero gels and silica glasses were prepared from hydrolysis and poly-condensation of precursor solution Tetra Ethyl Ortho Silicate (TEOS), which allows incorporation of specifications by sol-gel method. The xero gels were characterized by XRD, TGA, FTIR & UV/VIS absorption spectra. The intensity and the behavior of the radiation-induced bands are seen to depend on the type of the 3d- transition metal in presence of Neodymium. The host silicate glass shows the stabilizing effect due to increase of more color centers on Gamma Radiation. Reduction in spectroscopic parameters (Racaah and naphelauxetic ratio) confirmed the increase in covalent character of the transition metal ion in the silica matrix due to irradiation.