For the purpose of developing new-typed multifunctional composite nanofibers, novel color-tunable luminescence composite nanofibers endowed with simultaneously tuned electricity-magnetism performance have been successfully fabricated via a facile one-pot electro-spinning technology. The obtained trifunctional composite nanofibers are composed of polyvinyl pyrrolidone as the matrix, Tb(BA)(3)phen and Eu(BA)(3)phen (BA = benzoic acid, phen = phenanthroline) complex as luminescence materials, Fe3O4 nanoparticles (NPs) as magnetic materials, and polyaniline (PANI) as electrically conductive material. The results indicate the emitting color of the composite nanofibers can be tuned by adjusting the mass ratios of Tb(BA)(3)phen, Eu(BA)(3)phen, Fe3O4 and PANI in a wide color range of red-yellow-green under the excitation of 307-nm single-wavelength ultraviolet light. The electrical conductivity and saturation magnetization of the composite nanofibers can be respectively tunable by adding various amounts of PANI and Fe3O4 NPs. The nanofibers are expected to possess many potential applications in areas such as color display, nanodevices and biomedicine.