A mixer circuit includes: a mixer circuit including a first transistor pair to output a first differential input signal and a second transistor pair to output a second differential input signal by inversing the first differential signal; a local signal supply circuit to supply a pair of local signals to gates of the first transistor pair and the second transistor pair; an operational amplifier including an input pair coupled to an output pair of the mixer circuit and an output pair coupled to the input pair via feedback resistors, the operational amplifier to amplify the first differential input signal and output a differential output signal; a common mode feedback circuit to control a center voltage of the differential output signal so that the center voltage maintains a common voltage; and a common voltage generator circuit to generate the common voltage according to an amplitude of the local signal.