The therapeutic effects of traditional Chinese medicine(TCM) decoction is closely related to its decocting methods. A correct understanding of the scientific connotations of decocting methods in TCM is of great significance for guiding the application of decoctions and the development of modern TCM preparations based on decoctions. The decocting process is not only a hot water extraction process of chemical components but also accompanied by complex chemical and physical changes, forming a complex multiphase system and significantly affecting the absorption and therapeutic effect of TCM. This article reviews the research progress in scientific connotations of decocting methods in TCM from the perspectives of chemical composition changes, phase state differences,absorption behavior changes, and pharmacological and toxicological changes caused by decocting. This review is expected to provide implications for studying decocting methods and their scientific interpretation, boost the innovation and development of TCM decoctions,and promote the design and development of modern TCM preparations.