Erectile dysfunction (ED) is a global sexual disease of males characterized by a poor impact on many aspects of the lives of both husbands and wives. Although the incidence of ED rises significantly with age, the authors reported that fifty to seventy percent of males in the age range of fifty to seventy years were normal as regard erection. Despite the high magnitude of the problem, not all patients search for medical advice; only 50 % of them interested in solving the problem. The authors classified erectile dysfunction into two categories, one occurs in males with decreased sexual desire and the other occur with normal desire. As regards the aetiology of erectile dysfunction, the authors classified the causes as arteriogenic, venogenic, and neurogenic. Also, there are other causes such as anatomical, hormonal, and drug-induced. Some patients with ED may complain of psychogenic factors. The role of microRNAs in erectile dysfunction is a recent theory. MicroRNAs (miRNAs) are ribonucleic acids with 22 nucleotides in length that are characterized by being single-stranded non-coding molecules. Nowadays, these single- stranded RNA molecules play a role in the development of different disorders. These disorders are related to miRNAs molecules: cardiovascular disease, diabetes, neurological dysfunction, and metabolic syndrome. MiRNAs have an essential role in male infertility and ED. MiRNAs may be as biomarkers and novel therapeutic targets for ED. The mechanisms that may explain the role of miRNA in ED include apoptosis, fibrosis, angiogenesis, and other mechanisms.