In an imaging device, a pixel signal processing circuit outputs an imaging signal based on a pixel signal. A level shift circuit shifts a first level of the imaging signal in a direction in which the first level is away from a second level of a reference signal or shifts the second level in a direction in which the second level is away from the first level. A signal output terminal outputs the reference signal and the imaging signal, the first level of which is shifted, to an imaging signal processing circuit or outputs the reference signal the second level of which is shifted, and the imaging signal. The imaging signal processing circuit calculates a difference between the reference signal and the imaging signal output from the signal output terminal.