Enzyme activity and peripheral neutrophil function status in 32 male smokers was assessed. The studied subjects smoked 15-25 cigarettes 11-24 years. Histochemical methods allowed to assess activity of 10 enzymes. The following neutrophil function tests were carried out: latex phagocytosis, spontaneous and stimulated NBT, adhesion and agglomeration. Activity of 4 lysozymes was decreased. Also the following functional tests were abnormally decreased--latex phagocytosis, agglomeration. After stimulation lowering of activation of oxy-reductive processes were observed. The suppressive effect of tobacco smoke on enzyme activity and neutrophil function can effect the smokers defence mechanisms.