An integrated circuit device of the present invention includes a plurality of signal processing circuits classified into a plurality of groups, each signal processing circuit including an amplifier circuit for amplifying an input electric signal and a bias circuit having an input terminal connected electrically to a bias source and supplying a bias input terminal of the amplifier circuit with an operation bias for an amplifying operation of the amplifier circuit; and a plurality of connection wirings arranged each for each of the groups separately, such that the input terminals of the bias circuits of the signal processing circuits in one of the groups are commonly connected through the connection wirings. This provides an integrated circuit device suppressing the lowering of an image quality in consideration of enabling lower power consumption, a low noise characteristic, and high integration, and an imaging apparatus using the integrated circuit.