The aim of this study was to evaluate the effects of recombinant human erythropoietin (Epo), testosterone ( T) or a combination of them in the treatment of erectile dysfunction (ED) in hemodialysis patients, as well as the efficacy of sildenafil in patients unresponsive to combination treatment. A total of 23 patients with ED were divided into two groups. The international index of erectile function (IIEF) was used to evaluate ED and treatment response. Patients received Epo or T treatments for 12 weeks. Later on both groups received combination treatment for another 12 weeks. Although IIEF scores increased significantly in both groups after the combination treatment, the score changes were similar. After combination treatment, 16 patients still having IIEF score <26 were given sildenafil treatment in combination with Epo while T was discontinued. Although the IIEF scores increased significantly in all patients (17.4%), only eight of them attained an IIEF score of >= 26. The baseline IIEF scores of the patients with satisfactory response to the sildenafil treatment were higher than those with unsatisfactory response. The patients with a score of >= 22 responded better to the treatment. Although Epo and/or T therapies could partially improve ED in male dialysis patients besides correcting renal anemia and hypogonadism, sildenafil treatment could improve ED in unresponsive patients. Especially, those with higher baseline IIEF scores benefited more.