Efficacy of complex spa therapy was studied in 55 patients with bronchial asthma. Complex spa therapy was effective in 47 (85.5%) of the 55 patients with bronchial asthma : marked efficacy was observed in 15 (27.3%), moderate in 32 (58.2%), slight in 6 (10.9%) and no efficacy in 2 patients (3.6%). Improvement of clinical symptoms and findings by complex spa therapy was more clearly observed in patients with an increased proportion of BAL lymphocytes, neutrophils and eosinophils. These findings suggest that complex spa therapy more affects cell infiltration in the airways than bronchoconstriction induced by chemical mediators. Improvement of ventilatory function represented by FEV1.0% value was higher in patients with a low proportion of BAL neutrophils, suggesting that patients with increased number of BAL neutrophils require longer complex spa therapy than those without BAL neutrophilia.