Diabetes refers to the disease with the main symptom of “three more and less.” Traditional Chinese medicine (TCM) regards Yin deficiency and dryness heat as the basic pathogenesis, and mostly adopts the method of clearing away heat, nourishing yin and generating fluid. The author thinks that the deficiency of Yuanyang in Zang Fu organs, the lack of stimulation and promotion, the metabolic disorder of body fluid, the loss of moistening of Zang Fu organs, and the onset of diabetes. Body fluid metabolism is closely related to the spleen and kidney. Deficiency of Yang Qi is the root of thirst, stagnation of body fluid and Qi is the pathogenesis, and thirst is the final result.