Abstract: A heat dissipation system for a high-speed train running in a low-vacuum tube is provided. Component groups that provide power and resistance for the movement and stop of a train are provided at a periphery, close to the train, in a low-vacuum tube. The component group is provided with a group A cooling assembly. The group A cooling assembly includes a group A cooling-type heat exchanger and/or a group A nozzle assembly attached to the back of the component group. Since the friction between the train running at high speed and the air in the low-vacuum tube and the operation of the key equipment in the low-vacuum tube will generate a lot of heat, the group A cooling assembly in the component group in the low-vacuum tube exchanges the heat with the air in the low-vacuum tube.