The electrochemical and electroluminescent properties of some europium complexes and the terpolymers of 9-vinylearbazole．methyl methaerylate and europium-methacrylate complex were investigated．Cyclic vohammetry measurements of poly(VK-co-MMA-co-Eu(BA)2(MAA)phen)(C1) showed a quasi-reversible oxidation peak with onset of 0.75 V

and an irreversible reduction peak with onset of -1.8V．The msults demonstrated that this kind of multi-functional material has both hole- and electron-transporting properties．Some light-emitting diodes(LEDs) based on the europium containing complex and copolymers were fabricated．All these devices exhibited characteristic sharp red electroluminescence when forward biases were applied

and the turn-on voltage was in the range of 12～27 V．A maximum brightness of 52 cd/m2 with a luminous efficiency of about 0.031 lm/W was achieved from a single-layer device based on the multi-functional eopolymer C3．EL spectra of the devices showed that the emissions were from the corresponding lanthanide-complex units．instead of carbazole groups of the copolymers．It is suggested that the carbazole groups in Cn sewe as hole-transport material while electron transfer may occur thmugh the lanthanide-containing moieties of the same copolymer.