To obtain an electromagnetic filter that shields only an electromagnetic wave with a specific frequency received through a wall face and a window glass plate or the like of a building or a vehicle or the like.

In the electromagnetic wave filter, one filter element 1a or an array consisting of a plurality of the filter elements 1a are provided on an insulation board, the resistance resulting from the conductor loss of each filter element 1a has a reciprocal of the conductivity, which is the same as the radiation resistance at the resonance of no loss lines having the same size. Or each filter element above includes a resistor in its part, and the resistor has the same resistance as the radiation resistance at the resonance of no loss lines with the same size as the filter element.