To provide a radio wave absorption material and a radio wave absorber wherein their radio wave absorption characteristics are excellent, and their thicknesses can be reduced, and further, they can be used in the frequency band not lower than 5-6 GHz.

By mixing in a kneading way a 60-70 pts. mass ferrous oxide powder having its average grain size not larger than 50 μm with polypropylene having its mass ratio of 85: 15 to this powder, the mixture is so subjected to a thermal-press molding as to create a radio wave absorption layer of o.3 mm in its thickness. Thereafter, the radio wave absorption layer is so joined to a stainless steel plate subjected to a gold plating as to make it a radio absorber. The absorption characteristic of this radio absorber has been measured by a free-space method within the frequency range of 50-75 GHz. As a result, its absorption quality has been 39 dB at 60 GHz and its relative frequency bandwidth has been 7 % so as to obtain its excellent absorption characteristic, and its very reduced thicknesses of 0.3 mm has been made possible too.