Two novel Tb(III) ternary complexes with 2-aniline carbonyl benzoic acid (HAB) as the first ligand, imidazo [5,6-f] phenanthroline(IP) and 1,10-phenanthroline(phen)as the secondary ligands were synthesized. The structures of the ligands and Tb(III) complexes were confirmed by elemental analysis, IR spectra and UV spectra. The fluorescence spectra suggested that the luminescence intensity of Tb(HAB)3IP was obviously higher. Further investigation showed that HAB was the donor of energy, IP and phen which functioned as “energy ladder” could transfer the energy in the system of ternary complexes. If this “energy ladder” was located suitable, it could bridge the energy level difference between the triplet state of first ligand and excited states of rare earth ion .So, the intramolecular energy could transfer efficiently to central Tb3+ ion and competitive luminescence of HAB was also reduced.