Based on traditional Chinese medicine theory and clinical experience, traditional Chinese herbal drug toxicity has its own special connotation. From the perspective of history and logic, the different comprehension of toxicity between Western medicine and traditional Chinese medicine was discussed after retracing the meaning of "drug toxicity" in traditional Chinese medicine. The authors suggest that it's not feasible to study the Chinese medicine coping mechanically and applying indiscriminately the concept and the research idea about modern drug toxicity since there is different understanding of "drug toxicity" between traditional Chinese medicine and Western medicine. Many control elements are involved in the use of traditional Chinese herbal drugs, and Chinese drug components and actions are complex as compared with Western drugs. More and more drugs with toxicity will be found due to the relativity of drug toxicity. Currently, the study of Chinese drug toxicity should pay more attention to the relation between the toxicity and Chinese drug nature, compatibility and the corresponding disease or syndrome pattern after making definition of Chinese drug toxicity and its connotation.

Key words: Drug toxicity, Traditional Chinese herbal drug, Chinese medical formula