Symptom in TCM is named "sign" for short,including subjective symptom and objective sign,which is the objective reflection of pathological changes occurred in human body and is the basis of the formation of pattern of syndrome and treatment based on syndrome differentiation in TCM.The study of the normalization of symptom in TCM is one of the most important contents of the TCM basic theory research.This article from linguistics visual angle,through the objective analysis on symptom describing language of 21 ancient medical books before the Tang Dynasty,found that symptom language in TCM implicated logical rule under numerous and unordered appearance,that was presenting multiple grammar forms,basically fixed presentation mode and important effect of double words and metaphor in the symptom presentation etc.Among the total,three grammar forms are easy to normalize,and they constitute the most foundational nomenclatures of symptom in TCM.Meanwhile,the normalization of symptom in TCM is a complicated project,only with omnibearing and multiple visual angles,can it gain plentiful and substantial achievement.