γ-Fe2O3/Ni2O3 composite nanoparticles coated with 2FeCl3?5H2O were obtained from the FeOOH/Ni(OH)2 precursor prepared by co precipitation and then processing in boiled FeCl2 solution.The composite nanoparticles processed in different concentrations of FeCl2 were investigated by vibrating sample magnetometer (VSM)，X ray diffraction(XRD)，transmission electron microscopy(TEM) and X ray photoelectron spectroscopy(XPS) techniques，and their microstructure and magnetic properties of composite nanoparticles were revealed.The experimental results showed that the magnetization of the as prepared products varied non monotonically as the FeCl2 concentration increased.The effects of FeCl2 concentration on magnetization，morphology and chemical composition of the as prepared products were investigated.