Box-type vehicle-mounted control device

Provided is a box-type vehicle-mounted control device which efficiently increases the amount of heat transfer from electronic components and a circuit board to a housing (a base and a cover), and which has superior heat radiating properties. The box-type vehicle-mounted control device is provided with a circuit board (12), a base (13), and a cover (14), a first heat-radiating coating layer (31) is formed on at least one side of the circuit board (12), and a second heat-radiating coating layer (32) is formed on the inner surface side of the base (13) and/or the cover (14) facing the first heat-radiating coating layer (31).