One of the most important characteristics of chronic renal failure (CRF) is its progression to end stage renal disease. CRF progression depends of many factors indicated in numerous experimental and clinical studies. The present study was undertaken with the aim to examine the role of sex, etiology of CRF, renal function at the beginning of the study, hypertension and protein intake on CRF progression. Ninety-two patients (47 female and 45 male) aged between 17 and 70, with various underlying kidney diseases and various degrees of CRF were followed for 8 years. CRF progression was expressed as Creatinine clearance (CCr) and reciprocal values of serum Creatinine (SCr) against time. CRF progression was slower in women than in men, but not significantly. Patients with diabetic nephropathy (b = 0.00006) and glomerulonephritis (b = 0.00005) had faster progression of CRF than patients with nephrosclerosis (b = 0.00002), tubulointerstitial nephritis (b = 0.00003) and polycystic kidney disease (b = 0.00003). The fastest progression of CRF was in patients with the lowest SCr values at the beginning of the study. Proper regulation of blood pressure was the most important factor in slowing down CRF progression, independently of kind of antihypertensive drugs. Neither angiotensin converting enzyme inhibitors (b = -0.00001) nor calcium channel blockers (b = -0.00002) showed better effects on CRF progression slowing down in comparison with other antihypertensive drugs (b = -0.00001). Low protein diet slowed down CRF progression, but not significantly. In conclusion, our retrospective study confirms that CRF progression depends on sex, underlying renal diseases and serum Creatinine levels at the beginning of the study. Good regulation of blood pressure and low protein diet can slow down CRF progression.