Clinical features of bronchial asthma in the elderly were analyzed by observlng IgE-mediated allerglc reactions evaluated by immediate skin reaction and specific IgE antibodies to allergens, ventilatory function and cellular composition in bronchoalveolar lavage (BAL) fluid. 1. The frequency of positive immediate skin reaction and positive RAST score to allergens was in general low in the elderly patients over age 70. 2. Ventilatory function was widely variegated, and fifteen cases (60%) of the 25 Subjects showed considerably high values of FEV(l.0%), % PEFR, % MMF, % V(50) and % V(25), and the mean value of FEV(1.0%) in these cases was 71.3%. 3. The decreased value of % V(25) was related to BAL neutrophilia in 2 cases, but any correlation was not found between BAL neutrophilia and decreased value of % V(25) in 9 csese of the eleven subjects who had the BAL examination. The results show that in asthma of elderly patients, IgE-mediated allergic reactions are weak, and that a decreased value of % V(25) can be observed without BAL neutrophilia.