<p>Provided is a radio circuit device which can minimize mixing/modulation disturbance of a reception circuit attributed to a transmission signal leak. The radio circuit device includes: a transmission baseband circuit (12) which outputs a transmission signal; reception circuits (14, 15) which input a reception signal as a differential RF signal; an envelope signal generation circuit (24) which generates an envelope signal obtained by squaring the envelope signal of the RF transmission signal from the transmission signal (12) outputted from the transmission baseband circuit; an envelope signal control circuit (20) which outputs a control signal for controlling the amplitude and the delay time of the envelope signal; and an envelope signal implantation circuit (23) which controls the amplitude and the delay time of the envelope signal according to the control signal outputted from the envelope signal control circuit (20) and implants the controlled envelope signal in the same phase as the differential RF signal of the reception circuits (14, 15).</p>
