Active cooling must be utilized to meet the need for the space-based telescope which need very low detector noise level. The precise thermal control measures based on thermo-electric cooling technique are utilized and especially the package system and heat rejection system of thermo-electric coolers and its cotroller system are designed respectively. The parasitic heat load to the detector and the heat path resistances are optimized to reduce the input power and the radiator size. Based on the Peltier effect and Joule effect and Frourie effect, the relations between the enviroments parameters and working parameters are analyzed. The enviroments parameters include the heat pumped requirements, the thermal resistance between the hot side and the sink and the hot side sink temperature, while the working parameters include the current, voltage and input power of coolers. The sensitivity between the heat loads, thermal resistance and the input power are especially researched. The qualification model of the telescope is developed and the thermal vaccum and balance test are accomplished. The test results show that the system design are appropriate and effective, the detector temperature is controlled at -75±0.2℃. Based on the test environments conditions and the cooler's working parameters, the thermal analysis model are discussed and corrected.These lessons can provide some reference for the development of thermo-electric cooling system of the similar space based telescope.