The magnetic and microwave absorption properties of Nd 2 Co 16.5 Si 0.5 and Nd 2 Co 16.5 Si 0.5 -paraffin composite have been investigated. The Nd 2 Co 16.5 Si 0.5 compound shows a planar anisotropy with a saturation magnetization of 114 emu/g at room temperature. The Nd 2 Co 16.5 Si 0.5 -paraffin composite exhibits a permeability of 2.1 at a frequency of 100 MHz, together with a microwave reflection loss (RL) up to -38 dB at a frequency of 4 GHz with a thickness of 2.8 mm and a qualified bandwidth (QB, RL ≤ -10 dB) of 3.2 GHz at a frequency of 14 GHz with a thickness of 1 mm. This composite exhibits both high working frequency and permeability due to its high saturation magnetization. A strong microwave absorption was achieved for the composite through a better impedance match. Hence, it is possible that this composite can be used as a high-performance thin-layer microwave absorber.