There are numerous applications for pyroelectric composite films in the medical, military and environmental applications field. The main purpose (focus) of this research is to fabricate higher efficiency thin films that are flexible like polymers. Polystyrene has attracted the attention of scientists for its interesting features and its superior physical and chemical properties. A solution casting approach was developed to obtain flexible ZnO doped polystyrene (PS) nanocomposite thin films which were highly transparent in the visible region and exhibited excellent UV-absorbing properties. Major characteristics of this material include rigidity, transparency, high refractive index, good electrical insulation characteristics, low water absorption, and ease of processing which makes important for many applications in industry. Among the many inorganic materials, zinc oxide, ZnO, has been intensively studied as a promising material for optoelectronic devices such as light emitting diodes (LED). Optical characterization of the polystyrene think films doped with ZnO shows the reduction in the bandgap and enhancement in other optical properties.