To prevent distortion characteristics of a microwave power amplifier from deteriorating, if the input carrier frequency spacing widens.

The microwave power amplifier comprises a source-grounded FET 1, a first difference frequency short circuit 201 connected to the drain of the FET 1 for short-circuiting at a difference frequency between carrier frequencies and a second difference frequency short circuit 202 connected to the gate of the FET 1 for short-circuiting at a difference frequency between carrier frequencies. The second difference frequency short circuit 202 is composed of a bonding wire 30 connected to a gate electrode terminal 2 of the FET 1 and a capacitor 29 connected at one end to the bonding wire 30 and grounded at the other end.