OBJECTIVES In addition to many traditional risk factors for coronary artery disease (CAD) development, enhanced oxidative stress and inflammation are serious conditions that may also be classified as novel risk factors. In the present study, we assessed the relationship between several parameters of oxidative stress status [malonaldehyde (MDA), superoxide anion (O(2)(-)) and plasma and erythrocyte superoxide dismutase (SOD) activities] with high sensitivity C-reactive protein (hsCRP) and fibrinogen as inflammation markers. DESIGN AND METHODS Oxidative stress status parameters, inflammation markers and lipid status parameters were measured in 385 subjects [188 coronary heart disease (CHD) patients with angiographically diagnosed coronary artery disease (CAD), 141 patients with occlusion >50% in at least one major coronary artery (CAD+) and 47 patients with occlusion less than 50% (CAD-), and 197 CHD-free middle-aged subjects (the control group)]. RESULTS The plasma MDA concentration and the level of O(2)(-) in plasma were significantly higher in combination with significantly lower SOD activity in the CAD+ group vs. the control group. By using multiple stepwise regression analysis, fibrinogen and hsCRP showed independent correlation with MDA. Binary logistic regression analysis indicated that both MDA and O(2)(-) were significantly associated with CAD development and adjustment for inflammatory markers weakened this association in the case of MDA. CONCLUSIONS The relationship between oxidative stress parameters and inflammatory species suggest their strong mutual involvement in atherosclerosis development that leads to CAD progression.