There is provided a low-cost satellite broadcast tuner capable of receiving and processing both a QPSK modulation signal and an FM signal while assuring simple connection of an LNB (low noise block) to the tuner. A single front-end section including an RF stage, a mixer, a local oscillator circuit, an IF stage, an AGC loop is used for both an FM detector and an I/Q quadrature detector, so that both the FM signal and the QPSK modulation signal are received and processed in the single front-end section. In the above case, power supplied to the FM detector for detecting the FM signal, and power supplied to a local oscillator circuit required for detecting the QPSK modulation signal is turned off when receiving the FM signal.