Various-thick indium-tin oxide films and dielectric distributed Bragg reflector (DDBR) were utilized in resonant cavity to obtain the tricolor resonant cavity organic light-emitting diodes (RCOLEDs). The Commission Internationale d'Eclairage (CIE) coordinate of the resulting red, green, and blue RCOLEDs was (0.528, 0.393), (0.315, 0.575), and (0.186, 0.076), respectively. Compared with the conventional white OLEDs, these tricolor RCOLEDs revealed higher luminance efficiency. Since the resonant effect was caused from the resonant cavity structure with properly designed DDBR, the color purity and cavity quality factor of the tricolor RCOLEDs were also improved by narrowing the emission spectrum band and reducing carrier lifetime. (C) 2013 Elsevier Ltd. All rights reserved.