Polyamide (PA) fabric loaded with magnetite (Fe3O4) nanoparticle film was prepared by a simple chemical coprecipitation method. The surface morphology, chemical and phase constituents, crystalline structure, magnetic behavior, thermal stability, and mechanical properties of the Fe3O4-coated fabric were determined by means of scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, vibrating sample magnetometry, thermogravimetric analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy, and tensile testing. The results show that a thin membrane of Fe3O4 nanoparticles was immobilized on the surface of THE PA fabric. The saturation magnetization of the Fe3O4-coated fabric was 27.5 emu/g. The onset decomposition temperature increased slightly, but the initial endothermic temperature decreased. The Fe3O4 nanoparticles were deposited on the fiber surface by mechanical anchoring action. (C) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012