PURPOSE: To obtain a terminator having a large input return loss at a microwave band by adopting the constitution such that an impedance when viewing a terminator from an input terminal of a π type fixed attenuator is matching with a characteristic impedance of a microstrip conductor.

CONSTITUTION: The constitution is adopted such that an impedance when viewing a terminator from an input terminal of a π type fixed attenuator is matching with a characteristic impedance of a microstrip conductor. That is, the reactance component of the termination section 1 and the reactance component of the π type fixed attenuator 2 are cancelled by connecting a λ/4 length line 3. Thus, the reactance component of the termination section 1 and the πtype fixed attenuator 2 are cancelled together at the input terminal of the πtype fixed attenuator 2. Thus, a terminator having a large input return loss at the microwave band is obtained.