The preparation and micwave-absorbing behavior of nanosize PSZFe magnetic particles were studied．Nanosize PSZFe magnetic particles were prepared as following：nanosize Fe particles generated by themal decomposition of Fe(CO)5 in organic solvents were encapsulated with synthesized polysilazane (PSZ) precursor and then irradiated under ultraviolet light．PSZFe particles were characterized by using transmission election microscope (TEM)

X-Ray powder diffraction(XRD) and vibrating sample magntometer(VSM)

and their microwave-adsorbing properies were measured by means of a vector network analyzer．The influence of the polysilazation layer on corrosion and magnetization of PSZFe particles and the relationship between polysilazation layer and micwave-absorbing behavior of PSZFe particles were investigated. Results showed that the average diameter of PSZFe particles was 30 nm

the structure of iron in PSZFe magnetic particles was α-Fe．The formation of a PSZ layer on nanosize Fe particles enchanced the corrosion resistance of PSZFe．In addition

PSZFe particles coated with 3 wt％ PSZ demonstrated high corrosion resistance and fine microwave-absorbing ability as well．The reflection loss was less than - 10 dB in the range of 9.8 ～ 16 GHz

and a reflection loss value of -20 dB was detected at 13 GHz．