The invention discloses application of clematichinenoside AR in preparation of medicine for treating or preventing inflammatory bowel diseases. A medicinal effect test shows that clematichinenoside AR has an outstanding effect of resisting the inflammatory bowel crohn diseases in rats, and can be used for developing a type of novel traditional Chinese medicines which are capable of resisting the inflammatory bowel diseases (including immune inflammatory bowel diseases and inflammatory bowel diseases caused by other reasons) and are high in treating effect and high in safety.