The purpose of this work was to define dependence of maintenance of myeloperoxidase (MPO) in plasma of blood of patients by the acute infarct of myocardium from the state of oxygen metabolism of neutrophils, which was estimated on activity of myeloperoxidases, superoxid-anion and catalase in cells and on maintenance by peroxigens. 19 is inspected practically healthy volunteers and 56 patients with the the acute infarct of myocardium. The got results testify that maintenance of MPO in plasma of blood of patients with acute infarct of myocardium depends on the functional state of neutrophils, which, in its turn, is related to the clinical features of patients. Low maintenance is associated exceptionally with low activity of MPO of neutrophils, and also other oxygen radicals. High maintenance of MPO in plasma accompanied low or high activity of MPO of neutrophils and is pathognomonic for patients with the acute infarct of myocardium.