Urinary symptoms of benign prostatic hyperplasia (BPH) may affect sexual function, considered by patients themselves to be one of the most important aspects of the disease. Though lack of consensus on the underlying mechanism involved, some hypothesis are accounted for this association, such as autonomic hyperactivity, decreased nitric oxide (NO) production in the prostate and penile cavernous muscle, as well as pelvic atherosclerosis and endothelial dysfunction. Although medical treatment with alpha-blockers and/or 5 alpha-reductase inhibitors are the mainstays of benign prostatic hyperplasia/lower urinary tract symptoms (BPH/LUTS), there are some contradictory bias on the effect of sexual function either erectile or ejaculatory function. alpha-blocker is currently recommended as a first line treatment of BPH. Since it will reduce the sympathetic overstimulation of prostate, it may also affect the similar pathway in penis. It has been suggested that alpha-blockers may improve sexual function in patients with BPH. However, among alpha-blockers, tamsulosin is associated with an increased risk of ejaculation disorders. Long-term use of 5 alpha-reductase inhibitors alone or combined with alpha-blockers will cause reduction of prostate volume and improved the clinical symptoms; however, it may associate with sexual problems, especially ejaculation disorders. Based on the already published data, the effect of a-blockers and 5 alpha-reductase inhibitors on the sexual function will be reviewed. Moreover, this may reinforce physicians to manage appropriately these two highly prevalent and bothersome conditions.