In the production of film capacitors, the temperature control of the capacitor hot press is very important. PID control algorithm is widely used in the capacitor hot press. However, traditional PID control algorithm often has difficulty setting parameters. It is not suitable for such a large hysteresis and nonlinear temperature control system. Through the research of traditional PID control algorithm, Particle Swarm Optimization (PSO) algorithm and fuzzy control algorithm, an improved particle swarm algorithm is proposed, and the Improved Particle Swarm Optimization (IPSO) algorithm is applied in the fuzzy PID temperature control system. The temperature control system is simulated by MATLAB. The research results show that the fuzzy PID temperature control system based on IPSO is superior to other temperature control system in terms of adjustment time, overshoot and anti-interference ability.