A flexible organic light-emitting diode (FOLED) was fabricated on an indium tin oxide (ITO) plastic substrate by inserting an UV-curable epoxy resin as a buffer layer between the plastic substrate and ITO film. The structure of the FOLED devices was ITO/NPB (50 nm)/Alq(50 nm)/Mg:Ag(100 nm). The surface morphology of three kinds of substrates was characterized by atomic force microscopy. The results show that with a spin-coated buffer layer, the surface roughness of ITO films on PET substrate decreased from 1.08 to 0.34 nm. With the assistance of UV-sensitive resin, the adhesive force between the plastic substrate and ITO anode was significantly increased. The maximum luminance of FOLEDs was enhanced from 2720 to4860 cd/m(2) at 12 V. (c) 2008 American Vacuum Society.