Abstract: It is believed that theory of qi-monism is the core of TCM theories， which guides the syndrome differentiation and treatment of TCM. The different differentiations methods of TCM， such as syndrome differentiation in accordance with eight principles， syndrome differentiation in accordance with five-zang organs， syndrome differentiation in accordance with qi， blood and body fluid and syndrome differentiation in accordance with six meridians， are all the methods used to understanding the pathogenesis of human body's yin-yang balance. In fact， TCM pathogenesis refers to understand the mechanism of health， occurrence and development of disease from the perspective and thinking of Chinese medicine. While， theory of qi-monism combined with theories of yin and yang， visceral manifestations， qi， blood and body fluid， six meridians， constitutes the epistemological basis of the holism of TCM.