Polymorphonuclear leucocytes (PMNL) isolated from the defibrinated blood of 44 healthy volunteers (20 no smoking subjects and 22 smokers) were examined for the presence of tobacco antigens using specific rabbit antiserum conjugated with FITC. In 11 persons from the smokers group PMNL were examined by the direct immunofluorescence technique, using appropriate antisera, as well as for the presence of IgG, IgM and C3. It was stated that the number of PMNL with fluorescent tobacco antigens rose significantly after exposure to tobacco smoke. The above cells were detected both in non-smokers and smokers venous blood, while their percentage was more important in the latter. IgG, IgM and C3 were found in PMNL of all 11 examined smoking subjects. In the authors opinion, tobacco antigens are phagocytized after penetration into the organism, either alone or in the shape of immune complexes formed with specific serum antibodies. The possibility of vascular injuries caused by the above complexes as well as the question of a presumed affinity of tobacco and solanaceae antigens are discussed.