resistors rl 1 to rl 4 have a same resistance value a bias circuit bc 1 is a circuit for supplying a bias current to the bases of the differential pair of transistors q 9 and q 10 through resistors r 9 and r 10 a bias circuit bc 2 is a circuit for supplying a bias current to the bases of the transistors q 1 and q 4 through a resistor r 11 the base of the transistors q 2 and q 3 through a resistor r 12 the transistors q 5 and q 8 through a resistor r 13 and the base of the transistors q 6 and q 7 through a resistor r 14 respectively vcc is a supply voltage of the circuit if current at which each of the second to fifth differential pairs operates is ib current at which each of the transistors of the first pair operates is 2 ib the mixer circuit of embodiment 3 which is configured as described above is formed as an integrated circuit arrangement on a semiconductor substrate as is the case for embodiment 1 the bias currents to the current switch circuits 18 a and 9 a and the bias current to the v i converter 14 a are supplied from a common source through current dividers 200 a.