The new complex Tb0.5 Eu0.5 (TTA)3Dipy was synthesized. By doping polymer PVK with Tb0.5 Eu0.5 (TTA)3Dipy, the EL device was fabricated with the structure of ITO/PVK: Tb0.5 Eu0.5 (TTA)3Dipy/PBD/Al using PVK: Tb0.5 Eu0.5 (TTA)3Dipy as the emitting layer. Compared with the blend PVK: Eu(TTA)3, the Tb3+ acts as an energy transfer bridge, which enhances the energy transfer efficiency between PVK and Tb0.5 Eu0.5 (TTA)3Dipy. As a result, the emission of Eu3+ is enhanced with the quenching of the emission of PVK. The process of energy transfer was studied.