The super wideband electromagnetic wave absorber in RF-A-PF type has been proposed, which can be used for an anechoic chamber, wall material to prevent TV ghost, etc, In this paper, $Ni_x-Mg_{0.1}-Zn_(1-x-0.1){cdot}Fe_2O_4$ Ferrite Powder has been fabricated. Using this, then, [$Ni_x-Mg_{0.1}-Zn_(1-x-0.1){cdot}Fe_2O_4$-Rubber composite for RF-layer in the RF-A-PF type absorber has been fabricated and its characteristics has been analyzed. As a result, it has been shown that the $Ni_x-Mg_{0.1}-Zn_(1-x-0.1){cdot}Fe_2O_4$-Rubber composit with the quantity $_x$ of $Ni_x$ between 0.5 and 0.6 is suitable for the RF-layer in the case of which the grain size is sub-micrometer order.