Emotional diseases refer to diseases caused by the imbalance of yin and yang，qi，and blood in the organs due to emotional stimuli.It can be summarized as both the occurrence and induction of diseases due to emotional stimuli.The occurrence of emotional diseases is closely related to the characteristics and physiological functions of the liver.The roles of liver in governing free flow of qi and storing blood are important foundations for regulating emotion.The key pathological mechanism leading to the occurrence of emotional diseases is the dysfunction of liver in governing free flow of qi and storing blood.Chaihu Shugan Powder，originating from Jing Yue's Collected Works(Jing Yue Quan Shu)，consists of Bupleuri Radix，Citri Reticulatae Pericarpium，Chuanxiong Rhizoma，Aurantii Fructus，Paeoniae Radix Alba，Cyperi Rhizoma，and Glycyrrhizae Radix et Rhizoma Praeparata cum Melle.Its main effects are soothing the liver，relieving depression，promoting blood circulation，and alleviating pain.Clinical observations have found that Chaihu Shugan Powder can be used to treat depression，Alzheimer's disease，sleep disorders，and other psychiatric disorders，as well as psychosomatic diseases such as premenstrual syndrome caused by psychological factors，thyroid diseases，and breast hyperplasia，with good efficacy.This article reviewed the clinical application and mechanism of action of Chaihu Shugan Powder in the treatment of emotional diseases，aiming to leverage the advantages of traditional Chinese medicine(TCM) in treating emotional diseases and provide support for the clinical work of TCM in treating emotional diseases.