The aim. Evaluation of the TiO2 effect on the phagocytic activity of peripheral blood neutrophils. Materials and methods. 17 people were examined - 10 people with atopic bronchial asthma (m/f - 5/5, mean age - 38 [28, 48]), verified according to the international criteria, the second group (control) - 7 people - healthy controls (m/f - 3/4, mean age - 23 [21; 26] years). The phagocytic index and neutrophil activity in the NBT-test were calculated for all the examined patients. 0.008% solution of TiO2 (based on 1 mg / kg of body weight) was added to the test-samples, control samples were added with the physiological solution, standard samples - with a suspension of killed Staphylococcus aureus. All the samples were incubated for 30 minutes at 37°C, the ready smears were microscopied with counting the amount of formazan-positive granulocytes in the NST-test and cells that absorbed 1 or more Stf particles per 100 granulocytes. Results. TiO2 stimulated phagocytosis of staphylococcus with blood neutrophils in 53% of the examined patients by 8-30% (p = 0.02). Under the influence of TiO2 activity of phagocytes significantly increased, in comparison with that in spontaneous NST-test (p = 0.0001), but was lower than induction by staphylococcus (p = 0.049). In patients with allergopathology, TiO2 stimulated phagocytosis of staphylococcus and neutrophil activity in the NBT-test was also effective, as was the culture of staphylococcus aureus (31.2% compared to 34.3%). In the healthy group, the TiO2 solution increased the activity of neutrophils in the NST-test, compared with the physiological solution (on average and in 71% of cases by 10-18%), but not so than the culture of staphylococcus (24%, compared to 39, 7%). Among healthy people, there was a correlation between the hereditary of allergy and the neutrophil activity in the NBT-test with TiO2 (0.78). Conclusions. It was found that 0.008% solution of TiO2 stimulated the activity of neutrophils in the NBT-test, both in patients with atopic bronchial asthma and healthy people after 30 minutes of incubation in a thermostat. In patients with allergies, TiO2 increased phagocytosis of staphylococcus, as well as metabolic activity of neutrophils so much as staphylococcus. A strong correlation was found between the hereditary allergies and the increased metabolic activity of blood phagocytes in the NBT-test with TiO2 in healthy individuals.