Erectile dysfunction (ED) is strongly associated with aging. With the rapidly expanding aging population and the increase in life expectancy, an increase in the prevalence of ED is expected in the years to come. Currently, the mechanism of ED is not fully understood. MicroRNAs (MiRNA) are endogenous small RNA molecules that control gene expression post-transcriptionally. It has been included in many in vitro physiology and pathophysiology processes, which also involved in the process of ED. This research was designed to investigate the differential plasma MiRNA profiles in ED and normal erectile function in older males. The results might tell us which MiRNA and how did it involved in the process of ED in aging.

Inclusion Criteria:

• older males with erectile dysfunction

Exclusion Criteria:

• have some other general diseases, e.g. hypertension, vascular diseases, depression, chronic kidney disease, diabetes.

Group I: older males came to our clinic for diagnosis and treatment of ED. Group II: older males came to our clinic for physical examination and the erectile function was normal.

Group III: young males came to our clinic for physical examination and the erectile function was normal.