Abstract: A fuzzy PID controller was designed to solve the problems of overshoot and long response time of traditional PID temperature control in hot pressing welding, and the sparrow algorithm（sparrow search algorithm, SSA） was used to optimize the parameters of the controller to improve the dynamic performance and adaptability of the controller. Combined with the working principle of hot pressing welding, the sparrow algorithm was used to identify the mathematical model of hot pressing welding control system, and the accuracy of the identification model was verified. The fuzzy PID control system was established based on the identification model, and the Sparrow algorithm was used to optimize the quantization factor and the scale factor. The simulation results show that the proposed method has shorter adjustment time and smaller overshoot compared with the traditional PID and the traditional fuzzy PID. In order to verify the effectiveness of the algorithm, the application effects of the three control algorithms are compared in the hot pressing welding power supply. The results show that the controller is more significant than the traditional PID and the traditional fuzzy PID algorithm in the temperature control process of the temperature stability and rapid rise of the temperature, more suitable for the temperature control system.