In order to improve photoluminescence properties, terbium complex Tb(acac)3phen (acacacetylacetone, phen-1,10-phenanthroline) was incorporated into polystyrene (PS), polyvinylpyrrolidone (PVP), and polymethylmethacrylate (PMMA) matrixes and electrospun into various aligned composite fibers. Their morphology, structure and photoluminescence properties were systematically characterized and studied. The results demonstrated that under the ultraviolet (UV) light exposure, the emission intensity for 5D4 --> 7F(J) of Tb3+ in the composite fibers considerably increased, while it was greatly quenched in the pure complex, implying remarkably improved photostability in the composites. The composite fibers also demonstrated much better temperature stability of photoluminescence over the pure complex.