The invention provides an electric control heat shield ontrack usage system comprising an illumination angle measure device, a data processing computer, an electric control heat shield, and an electric control heat shield controller; the illumination angle measure device is used for measuring the angle between sunlight and a track surface; the data processing computer is used for receiving measured data of the illumination angle measure device, and sending different orders to the electric control heat shield controller according to the measured data; the electric control heat shield controller is used for controlling the electric control heat shield to execute close or open orders; the electric control heat shield is used for heat radiation or heat insulation of satellite equipment. The invention also provides an electric control heat shield ontrack usage method, and the method can control the electric control heat shield to open and close according to illumination angle changes, thus improving electric control heat shield usage efficiency.