Abstract: Chiton composite nanofiber membranes were made with electrospinning instrument, the great surface energy of the nanofibres could be used to adsorb Fe3O4 nanoparticle so that the nanometer magnetic composite materials were prepared. The chitosan nanometer magnetic materials were investigated by scanning electron microscope (SEM), Fourier transformed infrared spectroscopy (FT-IR),X-ray diffraction (XRD) and magnetic testing, The resuit shows that the good Chiton composite nanofiber membranes was prepared,the magnetic testing showed the nanometer magnetic composite materials preserved propertises of the chitosan composite nanofiber membranes and had the surplus paramagnetic characteristics, their saturation magnetization could be 15.4 emu/g.