PURPOSE: To obtain an electrical radiation absorber, which can be easily manufactured pertaining to the outer wall of a building, by a method wherein a conductive member is mixed in the concrete of the outer wall of the building, the radio characteristic impedance of the mixture is made to roughly match with a radio characteristic impedance in the air, and an electromagnetic wave in broadcasting is absorbed without making an electrical radiation reflect.

CONSTITUTION: An outer wall 1 is constituted in such a way that a conductive substance is mixed in a concrete, which is a dielectric substance to be used as a parent material of the wall 1, and a radio characteristic impedance of the mixture is made to match as a value roughly equal with a radio characteristic impedance in the air. Here, the conductive substance is a carbon fiber, for example. Thereby, an electromagnetic wave 2 in broadcasting can be absorbed by an electrical radiation absorber 3 constituting the outer wall 1 of a building, can be prevented from intruding in spaces in rooms and a reflection of the wave 2 from the outer wall 1 can also be prevented.