Guizhi Decoction is known as the leader of the group，praised by the ancient sages of all ages.However，some people think that this statement has the suspicion of exaggeration.Therefore，this paper discusses the principle of Guizhi Decoction，that is to say，the root of Traditional Chinese Medicine(TCM)treatment lies in Yin and Yang，Guizhi Decoction is suitable for the principle of Yin and Yang，based on the coordination of Yin and Yang，and for the purpose of regulating Ying Wei; through the brief analysis of the clinical application of Guizhi Decoction in the five viscera system of liver，lung，spleen，heart and kidney，as well as the application scope of Guizhi Decoction and its addition and subtraction in modern medicine，modern medicine The research progress of Neo Confucianism shows that Guizhi Decoction not only has a solid theoretical basis，but also has a strong vitality in the clinical practice of traditional Chinese medicine and modern medicine，to prove that Guizhi Decoction is not only the ancestor of the group，but also is indeed worthy of the name.