The present invention relates to a micro-fog cooling device used for an electronic device. The micro-fog cooling device used for the electronic device comprises a water tank, a Venturi tube, a first micropump, a second micropump, an atomization cooling cavity, a miniature atomization disc, a gas phase working medium return pipe and a liquid phase working medium return pipe. The miniature atomization disc and a high temperature electronic element are installed in the atomization cooling cavity, the water tank is connected with the miniature atomization disc via the second micropump, and the top of the atomization cooling cavity is connected with the Venturi tube via the gas phase working medium return pipe. The Venturi tube is communicated with the top of the water tank via a connecting pipeline, the first micropump is also arranged between the water tank and the Venturi tube, and a water pan is arranged at the bottom of the atomization cooling cavity and is communicated with the bottom of the water tank via the liquid phase working medium return pipe. By the design, and by adjusting the speed of the micropumps, the micro-fog formation number is adjusted, so that the heat absorption capacity in a micro-fog cooling cavity is changed, and the heat exchange capability of the system is flexibly adjustable.