Objective: To conduct a textural research for the plant morphology

habitat

distribution and use of the traditional Chinese medicine (TCM) Kuao

in order to define the origin of Kuao. Method: Plant morphology and habitat and distribution and use of Kuao were consulted in dictionaries and medical literatures between Han to Qing dynasties. Result: The original plant of Kuao was confused in Chinese herbal medicine books

they were Elephantopus scaber

Cirsium chinensis

Lactuca tatarica

Patrinia villosa. Conclusion: The Flora of China and the Flora of Zhejiang were consulted for the geographical distribution and plant morphology

including the chemical constituents and the pharmacological action of C. chinensis. By comparing and analyzing the content of herbalism in the ancient documents and Chinese herbal medicine books

the origin plant of TCM Kuao shall be C. chinensis.