PURPOSE: To obtain a T-type fixed attenuator having a large return loss at a microwave band by connecting a capacitive element in parallel with a T- branch point arranged with 1st, 2nd and 3rd fixed resistors.

CONSTITUTION: An open stub 19 being a capacitive stub whose tip is open is connected in the middle of a microstrip line 13b connecting to T-shaped 1st-3rd chip resistors 17. Since the open stub 19 is capacitive, the reactance based on the physical shape of the 1st chip resistor 15, the 2nd chip resistor 16 and the 3rd chip resistor 17 at a high frequency is cancelled, an input terminal 11 and an output terminal 12 form a matching condition to improve the return loss. Thus the T-shaped fixed attenuator having a sufficient return loss in a high frequency circuit is obtained.