Melatonin is a neurohormone produced by the pineal gland that has a variety of regulatory and neuroprotective properties. Melatonin levels have been found to be disrupted in some neurodegenerative disorders, including stroke, Alzheimer's disease, and Parkinson's disease, implying that it plays a role in the pathophysiology of these diseases. Its properties make it a promising potential therapeutic neuroprotective agent for some neurodegenerative disorders, with no side effects. The role of melatonin in the pathophysiology of some diseases is discussed and pinpointed in this review.