Abstract：WANG Bangcai carefully observes diseases and pays attention to finding the cause from the syndrome in clinical practice， and he has a unique understanding of diagnosis and treatment of chronic ulcerative colitis. He believes that damp- heat is an important pathogenic factor of the disease， and although the disease location is in the large intestine，it also involves the liver，lung，spleen，kidney and other zang organs. Clinically， the syndrome of the disease is mainly deficiency in origin and excess in superficiality；patients with chronic diarrhea who are difficult to be cured are mainly with syndromes of both deficiency and excess，mutual injury of yin and yang，and cold and heat in complexity. WANG proposes its treatment based on the idea of "combined treatment of the lung and intestine"，which includes that patients whose the upper and lower are mutually injured should be treated by diffusing the lung and clearing the intestine， and that patients with binding constraint of damp- heat should be treated by diffusing， unblocking and clearing the intestine. He regulates the constitution of people to prevent diseases under the concept of combination of the disease and constitution，and provides a new idea and method for Chinese medicine treatment of chronic ulcerative colitis.