To achieve reductions in size and weight and a higher functionality of an imaging device, the imaging device comprises a first circuit board mounting a first heat-generating component for processing a signal from the imaging sensor, a first heat dissipation plate for transferring heat from the first heat-generating component to the housing; and a fan disposed adjacent to the first heat dissipation plate, air-cooling the first heat dissipation plate, wherein the fan is configured to take in the air in a rotation axis direction and discharges the air in an outer circumferential direction, and the discharged air is blown to heat dissipation fins of the heat sink of the first heat dissipation plate and discharged from the discharge port.