Overall 94 patients with different patterns of pulmonary tuberculosis were examined for glutathione peroxidase (GP), glutathione reductase, glucose 6-phosphate dehydrogenase (G 6-PDH) and superoxide dismutase activity in neutrophils and lymphocytes. Chemiluminescence was used to study the capacity of neutrophils to generate free oxygen forms. Neutrophils showed functional deficiency of GP and G 6-PDH. The decrease of the oxygen-producing capacity of neutrophils, unbalance of glutathione-conjugated enzymes in lymphocytes were revealed either. The role of the alterations enumerated in the reduction of function of phagocytizing and immunocompetent cells in patients with pulmonary tuberculosis is discussed.