Eosinophilia characterized by accumulation of low-density eosinophils and high functional activity of normal-density eosinophils was detected in the blood from patients with bronchial asthma. Low-density eosinophils are characterized by low content of granules. In patients with bronchial asthma morphological and functional characteristics of bronchial eosinophils were similar to those of blood low-density eosinophils.