Total eosinophil count (TEC) was done in 13 normal subjects, in 8 subjects before and 90 mn after a "French" breakfast and in 29 asthmatic patients. The geometric mean is higher (p less than 0,001) in asthmatic than in normal subjects: 304 (231--391) versus 144 (101--197). The breakfast does not interfer with the result of the TEC. In asthmatic subjects, a significant inverse correlation appears (r = 0,57, p less than 0,01) between the logarithm of TEC and the quotient: formula; see text. This correlation persists whatever may be the subject's age, the duration of the asthma or age at which he first contracted the illness. Asthma appeared after 40 years in 4 of the subjects: their TEC was higher (p less than 0,01) than in subjects who had become asthmatic before the age of forty. The respiratory function was lowered more in these 4 patients than in others who had been ill for the same time (p less than 0,001). The TEC is not related to results of skin testine with usuel inhalant allergens (grass pollen, house dust, cat's or dog's dander) or by result of a provocation test (by inhalation of allergen). Eosinophilia and bronchial obstruction are connected by one (or more) factors that may be inhalant allergens in extrinsec asthma and circulating immune complexes in intrinsec asthma.