NaH promoted deprotonation of the NH groups in poly(benzimidazole)s, [-Im-C6H4-]n(1a) (Im: 5,5′-dibenzimidazole-2,2′-diyl) and [{-Im-(CH2)11O(CH2)11-}0.98{-Im-(CH2)10}0.02-]n(1b) followed by addition of 4 equiv. of EuCl3gave new soluble Eu complexes of poly(benz-imidazole)s (2aand2b) having N-Eu bonds in 66 and 42% yields, respectively. The Eu polymer complexes2aand2bhave two molecules of Cl and DMSO as ligands, which was revealed from IR and1H NMR spectra and elemental analysis. Energy transfer from the benzimidazole group in polymer main chain to the Eu(III) metal was occurred upon irradiation with UV light in the solid state. This resulted in light emission from both the polymer chain and the Eu(III) center, although the Eu(III) itself could not be excitated by irradiation with the UV light.