Provided is an imaging device which is capable of implementing noise countermeasures while efficiently dissipating heat emitted from an electronic circuit unit. The present invention is provided with: a housing 8 provided with an outer frame member 7 and a metal inner frame member 6; a lens unit 3 which is attached to an opening of the housing 8; a substrate 41 on which heat-dissipating metal wiring is formed; an electronic circuit unit 4 which is provided inside the inner frame member 6; and metal fixation members 9 which fix the electronic circuit unit 4 to the inner frame member 6 while being in contact with the inner frame member 6 and the heat-dissipating metal wiring 43 of the electronic circuit unit 4. Accordingly, heat can be efficiently dissipated from the electronic circuit unit 4 to the heat-dissipating metal wiring 43, the fixation members 9, and the inner frame member 6, and noise countermeasures can be implemented.