The NdFe absorbing powder was prepared by high-energy ball-milling and crystallization heat treatment. The influence of Si contents on the absorbing properties of NdFe powder was investigated. The result shows that the microstructures of Nd8Fe92, Nd8Fe89Si3 and Nd8Fe87Si5 powders consist of α-Fe, Nd2O3 and Fe17Nd2 phase after high-energy milling and 700 ℃, 1 h crystallization heat treatment in a micro-oxidation atmosphere. The relative amount of Fe17Nd2 phase increases after adding Si. The minimum reflectance of Nd8Fe92 powder is -4.5 dB, the frequency of the absorption peak is 4.4 GHz. After adding Si the minimum reflectance of powder decreases, while the frequency of the absorption peak increases and the absorption band of NdFe powder is widened. Nd8Fe92 powder takes dielectric loss, as main loss, while Nd8Fe89Si3 and Nd8Fe87Si5 powder take magnetic loss as main loss