A method of temperature and humidity control in double warehouses was proposed to design an automatic piling machine for dark tea which can realize the automatic adjustment of temperature， humidity and oxygen， numerical control and automatic operation in the piling process based on simulating the natural indoor pile fermentation methods of green brick tea and Pu-erh tea and the principle of water absorption and heat generation during piling fermentation and to solve the practical problems in the current dark tea production process. The results showed that the changes of temperature（average 51℃）， humidity （61%-89%）and the content of water in tea leaf （gradually reduced from 38% to 22%） in the pile fermentation process of the automatic piling machine fully met the requirements of dark tea piling. The tea leaves piled by the machine can meet the requirements of traditional processing methods， and the tea quality is stable. The results of safety analyses showed that no vomitoxin， aflatoxin B1 and zearalenone was detected in the dark tea piled by the automatic piling machine， indicating that the dark tea produced and processed by the automatic piling machine fully meets the requirements of food safety and tea quality.