To provide a radio absorptive compound with high permeability which is superior in radio wave absortion in a sub-microwave band of 300 MHz to 3 GHz.

This compound contains 15-30% (%: atom.%) in total of either or both of Al and Si, 3-15% Cr, and 0.5-5% in total of either or both of Sn and Sb, and a remaining part contains Fe and unavoidable impurities. An average thickness d is 0.5-3 μm, and when a particle size is assumed to be D50 at the time when the weight of particles is summed up to 50% from those having small particle size obtained by a particle distribution meter, D50 is 5-30 μm, and an aspect ratio (D50/d) is adjusted to 2-60. Such a flat metallic magnetic powder is sequestered in a flexible thermoplastic resin, a rubber or a binder which is blended with rubber and transformed, and they are arranged in the lengthwise direction.