Alzheimer's disease (AD) is one of the most common causes for the development of Dementia in the elderly. In past two decades there has been abundant research in pathogenesis of AD and possible prevention and treatment. The objective of this study is to evaluate the level of melatonin, and adipokines in patients with AD and control group. The study included 52 patients with AD and 52 healthy subject as control group. The results showed that serum melatonin, leptin, adiponectin, levels of patients with AD were significantly lower than the levels found for control participants (P < 0.0001). Patients with AD had significantly higher mean serum ghrelin, and resistin levels than the controls (P < 0.0001), there was positive correlation between adiponectin with leptin, and ghrelin. In conclusion, the results of this study showed that Circulating melatonin, leptin, and adiponectin were associated with a reduced incidence of AD, Resistin levels may be considered as a predictor of AD and it may predict activation of the immune system in AD pathophysiology.