Abstract: As the main glial cells in the central nervous system, microglia play a significant role in the pathogenesis of depression through changes in their number, morphology and density, which are mutually dependent on monoamine neurotransmitters, synaptic transmission, and inflammatory response. Studies have found that microglia can participate in the occurrence and development of depression by regulating monoamine neurotransmitters, synaptic plasticity, and neuroinflammation. Traditional Chinese medicine achieves the purpose of anti-depression by regulating the phenotype of microglial polarization, coordinating the pathogenesis pathways related to depression, and reducing the expression level of inflammatory factors. Based on this, this article reviews the research in order to provide new ideas for the study of non-neuronal pathological mechanisms of depression and provide a reference for the development of antidepressant drugs.