PURPOSE: To form a flat frequency attenuation characteristic by printing and forming a conductor pattern onto a prescribed insulator pattern in an insulator pattern, arranging a metallic piece on the prescribed insulator pattern in the insulator pattern by providing a clearance between insulator patterns, and providing a means to adjust the clearance.

CONSTITUTION: On an insulation substrate 15 composed of a ceramic material, input output conductor patterns 11 and 12 to constitute the attenuation element of a distribution constant type attenuation element, an earth conductor pattern 13 and a resistor pattern 14 are printed and formed. The attenuation element is of a structure to provide a metallic piece 18, in which one edge is electrically connected to an earth conductor pattern 13, and the size of a clearance (t) can be adjusted with a screw 19 for adjustment, in the clearance (t) at the upper part of an insulator covering 16. The capacity of the metallic piece 18 is operated as a capacity Cp to compensate a floating capacity Cs. The size of the capacity Cp can be changed by changing the clearance (t). Consequently, even in a high frequency area, a programmable variable attenuator having the attenuation frequency characteristic of the high attenuation quantity can be formed.