A semiconductor integrated circuit for radio communication includes a receiving-system high frequency block, a receiving-system voice band block, a transmitting-system voice band block, a transmitting-system high frequency block, and a power source control circuit for performing power source control to operate/stop each of the groups of circuits based on a power source control signal. The power source control circuit performs individual power source control for at least one circuit of the multiplier, the noise detector, the voice signal power amplifier, and the voice signal level detector, and also performs the power source control for each of the receiving-system high frequency block, the receiving-system voice band block, the transmitting-system voice band block, and the transmitting-system high frequency block, except for the at least one circuit subjected to the individual power source control.