The refractive index and UV spectra of the quaternary tellurite glass system of the form 80TeO(2)-5TiO(2)-(15-x) WO3-xA(n)O(m) where A(n)O(m) is Nb2O5, Nd2O3 and Er2O3, x = 0.01; 1, 3 and 5 mol% for Nb2O5 and x = 0.01, 0.1, 1, 3, 5 and 7 mol% for Nd2O3 and Er2O3. The refractive index has been measured at room temperature and at wavelengths 486.13, 587.56, 589 and 656.27 nm. The average dispersion (n(F) - n(C)), and Abbe number of this glass were estimated. The UV spectra of the glasses have been measured in the wavelength range of 200-1000 nm at room temperature. The relation between the refractive index and optical energy gap is examined. (C) 2008 Elsevier B.V. All rights reserved.