Abstract:The study of the root of Isatis tinctoria,a traditional Chinese medicine,has resulted inthe isolation and identification of ten compounds I-X .Six of them,uridine(Ⅰ),hypoxanthine(Ⅱ),uracil(Ⅲ),salicylic acid(Ⅳ),qingdainone(Ⅴ)and daucosterol(Ⅵ),were isolated fromthis plant for the first time.In addition,compounds I-Ⅳ have shown a certain activity ofinhibition on the blood platelet aggregation induced by ADP.