In order to reduce the influence of temperature change on the application quality of semiconductor pumped laser，a temperature control system based on thermo-electric cooler（TEC）is designed in this paper. The system uses STM32 as the core controller，and determines the temperature difference between the target temperature and the actual temperature of the pump module through the temperature sampling and control module. It combines the TEC power supply module and the main circuit module，and uses the PID algorithm to provide the TEC with appropriate driving current to heat or cool it. The temperature of the pump module is changed by the way of heat transfer. The stability of the pump module temperature is ensured through closed-loop control. Experimental result shows that the temperature control accuracy of the temperature control system does not exceed ±1 ℃，which has good stability.