A power amplifier according to the present invention includes: a carrier amplifier (2) that amplifies a carrier of a high-frequency input signal; a peak amplifier (3) that amplifies a peak component of the high-frequency input signal; an average power level detecting circuit (11) that detects an average power level of the high-frequency input signal; a peak power level detecting circuit (12) that detects a peak power level of the high-frequency input signal; a first voltage controller (10a) that controls a DC voltage supplied to the carrier amplifier (2) according to an output voltage signal from the average power level detecting circuit (11); and a second voltage controller (10b) that controls a DC voltage supplied to the peak amplifier (3) according to an output voltage signal from the peak power level detecting circuit (12).