To provide an airborne electronic apparatus casing expanding the cruising range of an aircraft.

This airborne electronic apparatus casing is provided with a thermoelectric transducer 23 absorbing heat from an electronic apparatus 21 by being contacted with the electric device 21 and applied with voltage, a case 4 wherein an electronic apparatus 21 and a thermoelectric transducer 23 are arranged, and piping 2 introducing a cooling medium 5 to the inside of the case 4. At this time, the thermoelectric transducer 23 has temperature higher than that of the electronic apparatus 21, and the temperature difference of the thermoelectric transducer 23 and the cooling medium 5 is larger than that of the electronic apparatus 21 and the cooling medium 5. Accordingly, the electronic apparatus 21 can be cooled more efficiently than when the cooling medium 5 contacts directly and cools, the bleed air flow of the bleed air for generating a cooling medium 5 is reduced and output loss of a jet engine is reduced to expand the cruising range of an aircraft.