Exosomes are vesicles released into extracellular cells by fusion of intracellular polyvesicles and cell membranes. Exosomes are secreted by a variety of cells and exist in a variety of body fluids. Exosomes contain proteins, lipids and nucleic acids, which can participate in the information exchange between cells. Exosomes secreted by CNS cells are involved in the occurrence and development of CNS diseases. Recent studies have shown that exosomes can not only serve as early diagnostic markers for CNS diseases, but also have therapeutic potential for CNS diseases. In this paper, the development, diagnosis and treatment of CSF exosomes in CNS diseases were reviewed.