The Theory of Leigong Baking is a work of traditional Chinese medicine written by Leigong in the Southern and Northern Dynasties and Liu and Song Dynasties. It is the earliest monograph on the processing of traditional Chinese medicine in China. It contains 300 kinds of drugs. Each medicine first describes the characteristics of the medicinal materials and the differences from the easily mixed varieties. It is an important document in the identification of traditional Chinese medicine. The original version of Lei Gong's baking theory has long been lost, and the existing version is compiled by later generations according to ancient books.