An imaging device includes an imaging element and a processor receiving subject light and generating data, a lens cover, an illuminometer, a light source emitting illumination light, an actuator switching the lens cover between a first state for restricting the subject light from entering the imaging element and a second state for allowing the subject light to enter, a switch including a first filter preventing the illumination light from entering the imaging element and a second filter allowing the illumination light to enter, to place the first filter or the second filter on a front surface of the imaging element based on a brightness level in a surrounding environment detected by the illuminometer, and a setter setting an amplification factor to be used by the processor in generating the data based on a brightness level in the surrounding environment detected by the illuminometer in the first state.