Abstract: The embodiments of disclosure disclose a thermal control system for a closed electronic platform, which includes two mutually independent heat exchange cavities; each heat exchange cavity is provided with an air inlet and an air outlet; one heat exchanger is arranged in each of the two heat exchange cavities; the two heat exchangers are interconnected with each other through guide pipes to form a working medium circulating loop; each of tow heat exchangers includes a plurality of microchannel thermo-capillaries and two runoff gathering pits; the plurality of microchannel thermo-capillaries are arranged between the two runoff gathering pits in a parallel connection manner; the runoff gathering pits of the two heat exchangers are connected through the guide pipes, wherein each of the plurality of microchannels which is arranged in parallel are formed in each microchannel thermo-capillary. Thus improving a heat dissipation efficiency of the thermal control system.