In this paper we have reported the optical and surface properties of semiconducting glassy thin films prepared by RF sputtering technique with argon gas plasma under vacuum from different compositions of 80B(2)O(3) + 15Na(2)O + (5 - x)MgO + xV(2)O(5):(0.5CoO) (x = 0.5, 1) glass targets. The changes caused by varying V2O5 ratios of glassy films on physical properties were examined. As a result of XRD analysis of obtained glassy thin films, these films were observed to have an amorphous structure. Surface characteristics were determined by atomic force microscope, absorption spectra were obtained by spectrophotometer and refractive indices were determined with ellipsometer. The fundamental absorption edge for the present glassy thin films has been analyzed using the theory proposed by Davis and Mott. Optical band gaps for direct and indirect transitions and Urbach energies were calculated and interpreted. (C) 2011 Elsevier B.V. All rights reserved.