Aiming at the lag, overshoot, easy interference, and other problems of the temperature control of the heat exchanger in the current alternating hot and cold treatment of deep vein thrombosis equipment, a fuzzy temperature control method based on Kalman filtering is proposed to complete the filtering for the measurement noise through Kalman filtering. Finally, based on the fuzzy strategy to achieve fast response and overshoot control of temperature control, we analyze its fuzzy rules and reasoning through the study of fuzzy PID control. By using MATLAB software for simulation and comparison, it is proved that the accuracy of the designed heat exchanger temperature control system is greatly improved, the robustness of the system is better, the response speed is obviously improved, the amount of overshooting is reduced, the regulation time becomes shorter, and there is also a strong inhibition effect on the interference.