Casting technique was employed for preparation of polyether sulfon (PES) films with and without various mass fractions of azo dye. Dependence of certain physical propertieswas correlatedwith filling level (FL). It is observed that upon increasing the azo dye concentrations, FTIR spectrum shows obvious changes in intensity and position of some bands. These results manifested the conclusion about the specific interaction in polymer matrices and hence the occurrence of complexation. UV-Vis. data indicate the presence of a well defined ð-ð* transition associated with the formation of conjugated electronic structure and the decrease in the optical energy gap was correlated to increase of the degree of disorder and overlap in the localized states. X-ray diffraction pattern (XRD) reveals the amorphous nature of the pristine and dye-doped polymer and shows the random distribution of the filler within the polymeric matrix. Scanning electron micrograph (SEM) suggests the dependence ofmorphological structure on dye concentration.