This aim of this study is to investigate the effect of UV (Ultra Violet ray) irradiation on the interfacial adhesion strength between thin ceramic films and polymer substrate. Electric conductive films based on polymer substrates have attracted attention for use in flexible optoelectronic devices. It is well known that the mechanical properties of polymeric materials are degraded by UV irradiation. Therefore, it is considered that the UV irradiation also affects the interfacial adhesion strength between ceramic coating and polymer substrate. The interfacial adhesion strength was measured by Multi-stages peel test. The results show that the interfacial strength decreases with UV irradiation. However, if a filter layer is installed between ceramic and polymer substrate, the degradation ratio becomes small.