Chronic Renal Failure (CRF) is a major public health problem. Early diagnosis and treatment are basic for its prognosis, and it will be fundamental for the future necessity of substitutive renal treatment. For this purpose, determining the etiology of chronic renal failure (CRF) may be helpful. This study was conducted in the Nephrology Department at the Central Military Hospital in Sana’a, Yemen from 2004 to 2007; to determine the etiology of chronic renal failure (CRF) in 334 patients (211 men and 123 women) on regular hemodialysis.