To provide an electronic device free of a risk that an electronic component is damaged by stress.

On an IC chip 3 mounted on a circuit board 2, a heat sink 6 is fitted through heat conductive silicone gel 5. A recessed portion 8a is formed on a reverse surface 8h of a housing body 8 opposed to the heat sink 6, and an upper end of the heat sink 6 is disposed in the recessed portion 8a. A plurality of springs 7 are interposed between the heat sink 6 and a bottom surface of the recessed portion 8a. Even if the circuit board 2 curves owing to variation in ambient temperature to generate stress pushing up the IC chip 3, stress applied from the circuit board 2 to the IC chip 3 and stress applied from the housing 9 to the IC chip 3 through the heat sink 6 can be relaxed, since the heat sink is displaced upward in the recessed portion 8a.