Background: Pruritus is one of the most disabling problems in patients with chronic renal failure. It is a distressing symptom with a negative impact on quality of life and is also very frustrating for both patients and their physicians. The pathophysiological mechanisms of pruritus are mainly unknown. The aim of this study was to identify factors associated with pruritus in these patients. Methods: This cross sectional study was done on 100 patients who were under hemodialysis because of end stage renal disease. In patients who were suffering from uremic pruritus, the severity of pruritus was assessed and the relationship between the presence and severity of pruritus with serum levels of hemoglobin, creatinine, urea, phosphate, calcium, albumin, parathormone hormone (PTH) and alkaline phosphatase was evaluated.Results: One hundred patients (48 women and 52 men) entered this study. Pruritus was found in 45% of the patients. We found a significant relationship between severity of pruritus with age and serum level of phosphate. No significant correlation was found between the severity of pruritus and sex, duration of dialysis, underlying renal disease and serum levels of hemoglobolin, urea, albumin, PTH, alkaline phosphatase, calcium, and creatinine. Conclusions: Pruritus is still a common problem in hemodialysis – dependent patients. Higher serum levels of phosphate seems to be an important factor associated with uremic pruritus.