A power amplifier includes amplifier elements to amplify input signals of different frequencies. The amplifier also includes a power supply circuit that includes a common power supply path including an end connected to a power supply input terminal connected to a DC power supply. The amplifier further includes individual power supply paths each including an end connected to the other end of the common power supply path, and the other end connected to the main electrode of a corresponding one of the amplifier elements. The individual power supply paths have different impedances.