Abstract：Ying and wei are the material basis of life-sustaining activities，which determines the dynamic balance between qi， blood， essence and fluids. The imbalance between ying and wei is a pathological state. The chapter Da Huolun of Ling Shu （The Great Perplexity Treatise of Spiritual Pivot） holds that the movement of the defensive qi （wei qi） is related to the body′s sleep-wake rhythm. Based on the theory of "imbalance between ying and wei，"this paper analyzes the mechanism of circadian disruption leading to type 2 diabetes mellitus， and puts forward the disharmony between ying and wei， that is， the essence of the imbalance of ying and wei， which leads to rhythmic disorders together with circadian disruption，affecting the process of glucose metabolism and hormone levels，and finally leading to the occurrence and development of type 2 diabetes mellitus. This article summarizes the treatment principles for this disease based on the theory of ying and wei and the biological rhythms， specifically focusing on harmonizing daily routines with the four seasons， avoiding overexertion， aligning with yin and yang and choosing optimal timing for therapy，and balancing ying and wei to open and disperse impediment.