Clinical features of asthma patients with bronchiolar obstruction (type Ⅱ asthma) were studied in relation to the proportion of neutrophils in bronchoalveolar lavage (BAL) fluid. Of 13 subjects studied, 7 were accompanied with BAL neutrophilia (53.5%) (BALn(+)) and 6 were without BAL neutrophilia (3.5%) (BALn(-)). 1. The mean age was higher in BALn(-) (66.0 years) than in BALn(+) patients (55.0 years). 2. Bronchial reactivity to methacholine was slightly higher in BALn(-) patients than in those with BALn(+). 3. The value of FEV1.0% was significantly lower in BALn(+) patints than in those with BALn(-) (p<0.01). 4. The proportion of BAL lymphocytes was signicantly more decreased in BALn(+) patients compared to the proportion in those with BALn(-) (p<0.001). 5. the values of serum IgG, IgA, and IgM were not significantly different between BALn(+) and BALn(-) patients, however, the value of IgG was more decreased in BALn(+) patients than in those with BALn(-). These results suggest that two kinds of type Ⅱ asthma ; one is with BAL neutrophilia related to suppressed immunity, and another is without BAL neutrophilia in part due to aging.