A new novel coprecipitate rare earths complexes La0.6Eu0.4(BSA)3phen has been synthesized and was chosen as the emitter material in the organic electroluminescent devices: ITO/PVK: La0.6Eu0.4(BSA)3phen/Alq/Al where PVK was used to improve the film-forming and hole-transporting property of the La0.6Eu0.4(BSA)3phen. It has been proved that it exists Förster energy transfer process from La3+ to Eu3+. This device has also been compared with the devices: ITO/PVK: Eu(BSA)3phen/Alq/Al and ITO/PVK: Tb0.6Eu0.4(BSA)3phen/Alq/Al. From the data, it indicated the device has the good purity of red color and good commutation property. The maximum EL brightness of 102 cd x m(-2) had been got.