ABSTRACT
Why the riddle of tri-jiao is discussed successively for thousands of years?Because it is too important,it is the formless original Qi,that has derivate relationship with materiality organs latently.The relationship is larger than the structural entity and function.The complex tri-jiao system arouses our highlight,exceeding the conformation anatomic entity of modern medicine;the research of systemic pleurodiaphragmatic interspace finds out the material tri-jiao structure.The structural levels of pleurodiaphragmatic interspaces and membranes:material structure of complex system of nine verticals,nine crossings,18 perverse-ring pleurodiaphragmatic interspaces and membranes.To further develop and set up unique structural levels of TCM human figure,the relationship structure and functional levels of tri-jiao membrane(9?9)?18m is of great importance connotation.