The natural drying process of chili peppers in Xinjiang Gobi Desert includes six steps which are hanging and drying， harvesting， spreading and drying， piling， sweating， bagging and transportation. However， the natural drying process is based on experience without technical protocol and theoretical guidance， in order that dried chili peppers are easy to be fragile and moldy. Therefore， it is necessary to monitor the natural drying process of chili peppers in Xinjiang Gobi Desert and develop its technical protocol， so as to standardize the natural drying process， ensure the safety and the quality of dried chili peppers. This study followed the natural drying process of three common varieties of chili peppers which were Honglong 18， Honglong 23 and Pepper Tiepi， and monitored the environmental temperature， humidity， wind speed， dry basis water content， water activity， color difference and moldy rate of drying chili peppers， and established a mathematical model of natural drying process of chili peppers in Xinjiang Gobi Desert. The natural drying process of chili peppers in Xinjiang Gobi Desert was in accordance with the Logarithmic drying model. Combined with the actual experience， this study regulated that the dry basis water content of peppers was about 1.0 g/g and 0.16 g/g when they were piled-up and at the end of natural drying. The determination of the dry base water content of chili peppers at the beginning of piling and the end of drying could provide a theoretical basis for the development of the technical protocol. In addition， this study found that mechanically harvested peppers were more damaged and more prone to mold in the natural drying process. Therefore， reducing the mechanical damage of peppers and standardizing the natural drying process were conducive to improving drying efficiency， ensuring the safety of dried peppers， and promoting the high-quality development of the dried chili pepper industry.