Compared to single functional materials, multifunctional materials with magnetism and luminescence are more attractive and promising; Thus, it has become an important subject. In our work, bifunctional Fe3O4/Tb(acac)3phen/polystyrene) microfibers with magnetic and luminescent properties (acac: acetylacetone, phen: 1,10-phenanthroline) were synthesized by simple electrospinning process. The doping of Fe3O4and Tb(acac)3phen made the fiber diameter larger. The surface of pure polystyrene microfibers and microfibers doped only with Fe3O4nanoparticles were chapped similar to bark, whereas the surface of the microfibers was smoother after doping with Tb(acac)3phen complexes. The luminescent properties of the composite microfibers were systematically studied in contrast to pure Tb(acac)3phen complexes, including excitation and emission spectra, fluorescence dynamics, and the temperature dependence of intensity. Compared with the pure complexes, the thermal activation energy and thermal stability of composite microfiber was significantly improved, and the luminescence of the unit mass of Tb(acac)3phen complexes in composite microfibers was stronger than that in pure Tb(acac)3phen complexes. The magnetic properties of the composite microfibers were also investigated using hysteresis loops, and an interesting experimental phenomenon was found that the saturation magnetization of the composite microfibers gradually increased with the increase in the doping proportion of terbium complexes.