Abstract: A cooling device capable of both power generation using heat from a heat-generating component and cooling of the heat-generating component is provided. The cooling device has a heat-receiving part which receives heat conducted from a CPU 20, which is an external heat-generating component, a thermoelectric conversion part arranged to absorb heat from the heat-receiving part and having operating modes including a mode of cooling the heat-receiving part by being supplied with a current and a power generation mode of converting heat received from the heat-receiving part into a current and outputting the current, and a selecting part which makes a selection according to a temperature condition of the CPU 20 as to in which one of the modes the thermoelectric conversion part should be operated.