An A/D converter circuit has an amplifier circuit to amplify an input signal and output a first amplification signal and a second amplification signal, the second amplification signal having an amplification error smaller than that in the first amplification signal, a first sampling circuit to sample the first amplification signal, a first A/D converter to perform A/D conversion on the first amplification signal sampled by the first sampling circuit and output a first digital signal, a second sampling circuit to sample the second amplification signal, a D/A converter to perform D/A conversion on the first digital signal and output a first analog signal, a subtracter to subtract the first analog signal from the second amplification signal sampled by the second sampling circuit and output a second analog signal, and a second A/D converter to perform A/D conversion on the second analog signal and output a second digital signal.