12-tetraphenyltetracene doped 8-hydrox-yquino line is as emitter are reported.The luminescence properties of the devices with different doped ratio were observed.The results indicated that there exists high effec-tive energy transfer from Alq to Rubrene:Alq
*
+Rubrene→Alq+Rubrene
*
→hν
and EL efficency of the single layer LEDs is hig her than that of Rubrene obviously.