Syndrome,disease and symptom of traditional Chinese medicine(TCM) are all summarization of some continuous events(event family)in panorama of single or composite cause and effect event induced by pathogeny. According to this theoretical framework,we can make the general judgment on the core reference range of disease,syndrome and symptom and the logical relationship between them. The scope of TCM syndrome roughly corresponds to the range of allostatic load described in western medicine,syndrome describes the pattern of allostatic load. All kinds of theories about syndrome in TCM history,actually have the inherent unity. They are aimed at the different stages of the continuous process of the whole body adjustment on adaptive responses and accompanied damage. TCM itself has two traditions as disease differentiation and syndrome differentiation,and seek the best combination of the two aspects. The primary significance of related discussion is to point out the field described by TCM syndrome and the characteristics of this field,which holds significant meaning to the scientific research of syndrome and clinical application,understanding of relationship between disease and syndrome,formation of the novel medical paradigm.