The efficiency and life time of flexible OLED are still major problem to overcome compared to the OLED devices based on glass substrate. The short life time of flexible OLEDs are attributed to the increased penetration of oxygen and water vapor to the thin organic layer of OLED device through the flexible polymer film substrate. In this work, we prepared glass fiber reinforced polymer film (GFRF) for use as substrate of flexible OLED. The glass fabric was immersed in the UV curable resin and packed between the transparent glass templates followed by UV irradiation for conversion to GFRF. The optical and mechanical properties of the GFRF films were examined and optimized for use as substrate of flexible OLEDs. The gas barrier layers were formed on the GFRF films. The deposition of ITO/Ag/ITO transparent conduction anode was carried out by using roll-to-roll sputter followed by fabrication of flexible OLEDs. The effect of process conditions on the property of flexible OLEDs were studied from the view point of application to the OLED lighting and signage of flexible OLEDs.