β-carotene is an important antioxidant substances and, it prevents the oxidation of the unsaturated lipids, so quenches the formation of free radicals (FR). FRs have an affectingly role in damage of enzymes, proteins and lipids in cellular membranes and tissues. Low serum concentrations of β-carotene may be a risk factor in the etiology of chronic renal failure (CRF). Therefore, we investigated serum β-carotene concentrations in 36 chronic hemodialysis patients with CRF and 20 healthy controls.Serum β-carotene concentrations in patients and controls were 108.47 µg/dl and 155.00 μg/dl, respectively.Serum values of this essential substance in the controls were significantly higher (P<0.005) than those of the patients.According to these data, low β-carotene levels in serum may play a role in etiology of the CRF.