Very limited data are available about the causes of renal diseases leading to chronic renal diseases in all states of Sudan, including Gezira state. Awareness of the cause of end-stage renal disease (ESRD) helps the nephrologists to anticipate problems during renal re-placement therapy and plan preventive measures for the community. Over 1.1 million patients are estimated to have ESRD worldwide, with an addition of 7% annually. This is a cross-sectional study designed to determine the etiology of ESRD among patients with ESRD on regular he-modialysis (HD) at Gezira Hospital for renal disease. This study was conducted in May 2009. The population examined here consisted of 224 patients on regular HD in Gezira Hospital for renal disease. We found that the etiologies were dominated by unknown causes (53.57%). The leading cause of ESRD for those who were younger than 40 years was glomerular disease, hypertension for those between 40 and 60 years and obstruction for those who were older than 60 years.