In an automatic gain control amplifier, an RF automatic gain controller controls the gain of a radio frequency signal. A frequency converter frequency-converts the radio frequency signal into an intermediate frequency signal. An IF automatic gain controller controls the gain of the intermediate frequency. A level detector detects a signal level of the gain-controlled intermediate frequency signal, and generates a level signal. An automatic gain control signal generator separately controls, based the level signal, the RF automatic gain controller and the IF automatic gain controller.