Highly efficient blue organic light-emitting diodes (OLEDs) were developed using diphenylamino-fluorenylethylene derivatives. In particular, OLEDs using compound 3 as a dopant in the emitting layer showed a maximum luminance of 12940 cd/m2 at 10 V; a luminous efficiency of 12.68 cd/A at 20 mA/cm2; a power efficiency of 5.24 Im/W at 20 mA/cm2, and CIE(x,y) coordinates of 0.181, 0.295 at 10 V. Furthermore, a deep blue OLED using dopant 2 with CIE coordinates of (0.154, 0.129) exhibited a maximum luminance of 5315 cd/m2 at 10 V; a luminous efficiency of 4.11 cd/A at 20 mA/cm2, and a power efficiency of 1.66 Im/W at 20 mA/cm2.