An imaging device includes an imaging optical system including at least one movable optical element; an image sensor, an imaging surface of which lies on an image-forming plane of the imaging optical system; a circuit board on which the image sensor is mounted; and an image processing circuit for processing an image signal output from the image sensor and a drive circuit for the movable optical element, both of the image processing circuit and the drive circuit are mounted on the circuit board. The image processing circuit and the drive circuit are disposed on the circuit board in that order from a side closer to the image sensor.