An imaging device includes an LED element mounted on a surface of an LED substrate and electrically connected to a wiring pattern. For the surface of the LED substrate, a heatsink for dissipating heat of the LED substrate is arranged to face the surface of the LED substrate on which surface the LED element is mounted. The heatsink includes: a base portion attached in a manner allowing heat transfer in which a heat transfer surface of the base portion faces the surface of the LED substrate, the base portion allowing the illumination light from the LED element to pass through the base portion; and fins integrally protruding from the heat dissipating surface, being arranged spaced from each other, and being cooled by air that is naturally convected.