An imaging device includes: a photoelectric converter including first and second electrodes, and a photoelectric conversion layer located between the first electrode and the second electrode; a voltage supply circuit applying a bias voltage between the first electrode and the second electrode: an amplifier transistor including a gate electrically connected to the second electrode, the amplifier transistor configured to output a signal corresponding to a potential of the second electrode; and a detection circuit configured to detect a level of the signal from the amplifier transistor. The voltage supply circuit applies the bias voltage in a first voltage range when the level detected by the detection circuit is greater than or equal to a first threshold value, and applies the bias voltage in a second voltage range that is greater than the first voltage range when the level detected by the detection circuit is less than a second threshold value.