Physical, optical absorption, ESR and DSC studies on 50 B2O3–(50−x) CdO–xTeO2 glasses containing Cu2+ spin probe have been carried out. Density measurement is carried out by Archimedes principle. Variation in glass transition temperature is discussed in terms of physical parameters. ESR results show that g∥>g⊥ indicating that the Cu2+ ions is in tetragonal distorted octahedral site and its ground state is dx2−y2. There are considerable changes in g∥, g⊥ and A∥ values with increasing the concentration of CdO in BCT glass systems. The optical absorption spectra results show that the absorption peak of Cu2+ is a function of composition. The observed optical absorption peak of Cu2+ has been found to be minimum at 776nm for x=30mol.% of CdO content. The variations in the physical, optical and bonding parameters clearly indicate the structural changes in the present glass system with varied CdO content.