Abstract: Based on the theory of fuzzy PID control, a high flexible intelligent controller is designed in combination with practical application. The controller uses a chip microprocessor to control temperature detection circuit. According to the real-time performance of the temperature control cabinet, the system adjusts the PID parameter online to improve its exactitude and make the control more sound and reasonable. The Matlab/Simulink system simulation software is used to simulate the common PID and fuzzy PID with the results comparatively discussed. It is thus revealed that the fuzzy PID controller designed has higher stead-state precision and faster response speed, as well as better overshoot. The serial communication is given between the chip microprocessor and upper monitor to strengthen the intellectuality and interaction of the detection system so as to meet designed request. The detection circuit and the serial communication program both have high universality and transplantability.