Oxidative stress refers to a well known pathogenic tool of cell lesions. This article aims at the identification of the circulating levels of the oxidative stress basic markers in patients undergoing coronary angioplasty. Before the stent implantation the activation of oxidative stress has been found in patients who need a coronary angioplasty, the fact that has been manifested by a significant increase (up to 118%) of malonic dialdehyde (MAD) and advanced oxidation protein products and by a significant decrease of glutathionreductase (GR) and superoxiddismutase (SOD) (within 19.75-26.8% compared to the indices of healthy persons). In the early studied period (60 min-24 hours) following the angioplasty such a significant rise of MAD as by 32.3% has been detected while the blood content of main antioxidant enzymes, GR, SOD and glutathionperoxidase has fallen by 10-24.6% in comparison with the pre-procedure values. Along with the oxidative stress activation, a significant decline of the nitric oxide concentration in blood has been found before the angioplasty, the amount of which becomes more conspicuous in the first 48 hours after the stent implantation. Generally the obtained data suggest that the traumatic impact of stent implantation on heart and coronary endothelium enhances free oxygen radicals production whose damaging action is poorly limited in the early period due to the antioxidant defense lessening. The decline of nitric oxide level, the predictor of endothelium injuring, mainly due to its anion superoxide metabolization, is correlated with the antioxidant enzymes reducing. So it is proven that DAM, SOD and glutathion-redox system enzymes are the markers of oxidative stress level assessment after angioplasty.