The incidence of neurodegenerative diseases (NDs) is increasing with the years, and current drugs targeting NDs are basically symptom-based, not therapeutic, so they can’t prevent disease progress. Exosomes are a subset of extracellular vesicles that can be produced by all cells in the human body and exert biological effects in a variety of ways after they are released into the extracellular environment. Many studies have shown that although exosomes have two sides in the central nervous system, they can still be used as a tool for the prevention, remission, treatment and diagnosis of NDs due to their unique biological characteristics. This article reviews the biogenesis of exosomes and their roles in neurodegenerative diseases, so as to provide new ideas for clinical treatment of NDs.