Generalized anxiety disorder (GAD) belongs to the category of emotional diseases in TCM, and its occurrence is closely related to liver depression and qi stagnation, and liver depression and fire syndrome is one of the TCM syndromes of GAD. With the deepening of modern medical research on GAD, microglia have been found to play an important role in the development of liver depression and fire syndrome of GAD. Excessive activation of microglia and transformation to M1 type would cause inflammatory mediator secretion up-regulation and destruction of neurons, etc. When using liver-soothing and heat-clearing medicines such as Bupleuri Radix, Gardeniae Fructus, Dangzhi Xiaoyao San, Yuejiu Pills and other Chinese materia medica or compounds, activation of microglia would be suppressed, and the inflammatory mediators mediated by microglia would also be suppressed, and the neurons could be protected. Therefore, this article discussed the modern biological connotation of the liver depression and fire syndrome of GAD from the perspective of microglia, and summarized the effects of TCM modulation of microglia on the liver depression and fire syndrome of GAD, and concluded that microglia could mediate the development of liver depression and fire syndrome of GAD.