Metabolic syndrome includes glucose intolerance, dyslipidemia, hypertension and obesity. Incidence of metabolic syndrome increases in our country and all around the world. Although the hypothesis of the role of metabolic syndrome in the etiology of prostate cancer, the epidemiological evidences are insufficient to suggest a link between metabolic syndrome and prostate cancer. There are few studies that contain all components of metabolic syndrome. Besides, there are many studies about the role of obesity in the etiology of prostate cancer as a component of metabolic syndrome but data are conflicting. Studies indicate that obesity is together with a minimal increasing in prostate cancer risk. Clearly, prospective studies are needed to exhibit the relationship between hypercholesterolemia and prostate cancer. Studies detected that prostate cancer is rare in diabetes mellitus group and support the role of insulin resistance in the etiology of prostate cancer. Nevertheless, existence of one-or two components of metabolic syndrome reflect metabolic syndrome is not clear.