Abstract Background erectile function is greatly affected in patients with chronic renal failure which manifest itself with various grades of erectile dysfunction which is reflected on physical and psychosocial health of the patients which has a significant impact on quality of life (QOL). Purpose to evaluate erectile function in CRF patients on regular hemodialysis versus post renal transplant patients. Patients and Methods the study included 50 patients recruited from urology and nephrology outpatient clinic in El Zaitoon and Naser Institute Hospitals during a period of 6 months. The 50 patients were divided into two groups: chronic kidney disease group (DIALYSIS) and renal transplant group (TRANSPLANT). Results the domains concerning the sexual performance of IIEF-5 showed that in our study erection function domain showed better results in renal transplantation group (p < 0.003) with median(IQR) in the CKD and renal transplant patients 10(40%) and 15(60%) respectively. Conclusion successful kidney transplantation can significantly improve ED in CKD patients, especially in individuals with a shorter time on dialysis. Changes in sex hormone levels may contribute to this improvement in ED.