Hemodialysis and peritoneal dialysis are methods of blood purification, which partially replaced excretory renal function in patients with chronic renal failure, which was depleted regime, dietary and pharmaco-therapeutic remedy, and who are not eligible for kidney transplantation. Both two methods are accompanied by increased oxidative stress. In peritoneal dialysis particularly the composition of dialysis solution contributes to oxidative stress. In extracorporeal hemodialysis the oxidative stress is associated with the character of hemodialysis membranes, non-specific loss of low molecular weight antioxidants, activation of leukocytes (oxidative burst), feroteraphy, supplementation with low molecular weight antioxidants and other factors. To improve and maintain the quality of life of dialysis patients, the continuous monitoring of oxidative stress-related parameters as non-traditional risk factors for cardiovascular complications development is suitable.