To realize a heat radiating device in which a case surface can be turned into high temperature in a relatively simple method while any danger on a human body or a setting place can be prevented, and the case can be obtained in a sealed form, and heat can be transmitted to the case and the heat can be cooled by natural convection and radiation.

At least one part of the case of an electronic equipment is composed of a metallic board 1, and a resin board 2 is provided so that the outside of the metallic board 1 can be covered. One sides of the metallic board 1 and the resin board 2 are connected so as to be opened and closed by a hinge 4, and the other side of the resin board 2 is pushed down by a restraining safety lug mechanism 5 while being linked with the opening motion of an outer cover 6 at the time of using the electronic equipment so that natural convection can be generated in a clearance between the metallic board 1 and the resin board 2, and the heating of the circuit part of the electronic equipment can be radiated.