In the 20th Century, modern pharmacology of traditional Chinese drugs (herbal pharmacology)has been developed by Chinese pharmacologists, clinicians and related scientists using modern technology.200~300 single active ingredients have been isolated and a number of them being used in clinics.Modern pharmacological actions of nearly 400 recipes have been investigated and a number of jounals carrying papers on herbal pharmacology have been published. The development of herbal pharmacology could be roughly divided into two periods in the 20th Century .In the first half of the Century actions of a number of herbs have been investigated and single compounds have been isolated.The dramatic event was the isolation and action study of ephedrine done by KK Chen. In the second half of the Century ,the study of herbal drugs has been carried out not only using modern technology but also under the guidance of the theory of TCM (traditional Chinese medicine).The emphasis has been put on the sutdy of a group (or category) of herbs and recipes.Based on these studies, theories of mechanism of action of herbs is emerging. It is hoped in the next Century that the new and systematic modern herbal pharmacology will grow mature.And it is anticipated that there will be a great leap forward in the future decades.