To realize great weight reduction while raising the rigidity of an entire of an electrical apparatus and at the same time effectively radiating the heat of the electrical component in an electrical apparatus such as mounted on a satellite.

In a heat radiating electrical apparatus having a plurality of printed substrates 20 whereon an electrical component 10 is mounted, and a housing 30 to store the printed substrates 20, a heat radiation layer 22 which is also used for a structural member is formed in the printed substrate 20 and a plurality of sides of the heat dissipating layer 22 are integrally fixed to the housing 30. Consequently the heat of the electrical component 10 can be radiated effectively, the housing 30 can be thinned by raising the rigidity of the entire of the heat radiating electrical apparatus and the weight of the electrical apparatus can be greatly reduced.