Abstract. Cardiovascular diseases remain the leading cause of death in recent decades worldwide, especially in developed countries. Cardiovascular pathology can begin with risk factors that can cause local vascular damage and end with systemic complications leading to organ failure and death, which makes it necessary to understand the biochemistry of events associated with the entire process of progression of cardiovascular diseases and is crucial for diagnosis, prevention and treatment. It is known that the state of blood vessels is influenced by multiple factors of hemodynamic conditions, extracellular signaling proteins, including interleukins, cytokines, and intracellular biochemical molecules, including reactive oxygen and nitrogen species. The aim of the work was to evaluate the factors of oxidative stress and antioxidant protection in patients with coronary heart disease. The study included 96 patients of working age with a verified diagnosis of coronary artery disease. Statistical analysis was carried out using the StatTech v. 2.6.5. To assess the diagnostic significance of quantitative signs in predicting a certain outcome, the method of analyzing ROC curves was used. The article presents data on the quantitative content of nitric oxide, myeloperoxidase, superoxide dismutase in the blood serum of patients with coronary heart disease (acute myocardial infarction and unstable angina pectoris), describes the relationship between changes in their level, and assesses the diagnostic significance of the studied parameters. The obtained data on the production of nitric oxide, myeloperoxidase and superoxide dismutase in patients with acute myocardial infarction and unstable angina indicate an important prognostic value of assessing oxidative stress and the antioxidant system for early risk stratification of adverse outcomes in patients with coronary heart disease.