An electromagnetic wave absorber comprising a surface layer (2) made of a composite of fibers having an electrical specific resistance of more than 10⁴ Ωcm and a resin, and a wave absorbing layer (3) made of a composite containing silicon carbide fibers having an electrical specific resistance of from 10⁻² to 10⁴ Ωcm. The composite used in the surface layer may be prepared, for example, by impregnating the resin in between the fibers after they have been treated to be a woven cloth, mat or felt or unidirectionally arranged fibers. If a wave absorbing layer is to be made of a composite containing the silicon carbide fibers and a resin, then the composite may be prepared in the same way as the above.