The membrane system is a multi-layered complex system composed of the whole membranous structures and their subsidiary tissues.According to whether it connects with the external environment，it can be divided into external membrane system and internal membrane system.The external membrane system serves a protective barrier function and is crucial for the exchange of substances，information，and energy between the body and the external environment.The internal membrane system is responsible for coordinating communication between various internal organs of the body，facilitating the exchange of substances，information，and energy within the body.The theory of membrane system can guide the clinical treatment of relevant diseases.The external membrane system is an important way to eliminate pathogenic factors.Sweating，vomiting，purging，and other methods can be used to eliminate pathogenic factors by regulating the distribution of qi and fluids in the external membrane system.The internal membrane system is an important way of disease transmission and transformation.Stagnation of qi and abnormal metabolism of fluids are the most common pathology.Treatment strategies focus on regulating the flow of qi and fluids within this system.When regulating the distribution of qi and fluid in the membrane system，special attention should be given to the qi movement in Shaoyang and middle energizer to restore the proper rise and fall of qi throughout the body.Renal membrane is the origin of the membrane system of the whole body.In the early stage of the membranous diseases，it is crucial to protect the renal membrane to safeguard areas not yet affected by pathogens.In the late stages of the disease，tonifying kidney yin and yang can address the root of the disease and protect the body's vital energy.