Neurodegenerative disorders continue to place the biggest strain on healthcare systems. Basic research is still being done on the molecular foundations of disease pathogenesis and initiation. Exosomes have only lately been connected to the onset and development of various neurodegenerative disorders. Exosomes, tiny extracellular vesicles with a bilipid coating around them, were once thought to be cellular trash that could help track the onset of neuro diseases. These ≤150 nm-diameter nano-vesicles contain significant non-coding RNA like circRNA, lncRNA, and miRNA; functional mRNA; and specific proteins and lipids. These vesicles can be used as a diagnostic indicator for early disease detection because the composition of exosomes is known to differ depending on their source and target cells. This article reviews exosomes’ biogenesis, composition, and roles in neuronal development, mental illness, and degenerative disorders. We also emphasize the possible use of neuronal exosomes as therapeutics for neurodegenerative diseases.