Abstract:It has been found through a textual study that the Cassia Twig recorded in ancient herbals before the Tang Dynasty seems to be the bark of the trunk and branches of Cinnamomum cassia, not the twigs of the above species often used nowadays. Today‘s Cassia Twig was originally named Liugui (willowy Cassia) and first recorded in the ancient herbal Bencaobieshuo of the Song Dynasty.