Abstract: This system is a closed-loop control system that uses PLC+human-computer interaction interface as the control core,based on PID control and fuzzy control,and uses fermentation temperature and humidity,and fermentation oxygen concentration as feedback signals.This system is equipped with a box-type black tea fermentation machine and was tested in a tea factory in Yingde.The result of the test is that the temperature and humidity control based on PID has strong robustness and is suitable for actual production use.Oxygen content control based on fuzzy control,due to its principle characteristics,plus many external interference factors,poor anti-interference ability,and relatively low control accuracy.