In order to assess the status of beta adrenergic receptors in bronchial asthma, binding studies using (-) [3H] dihydroalprenolol (DHA) were performed on lymphocytes of 10 control subjects and 11 stable asthmatic patients. Specific DHA binding was generally lower at all DHA concentrations in asthmatics. At 12 nM DHA concentration, specific DHA binding was 391 ± 40 fM/mg protein in controls and 263 ± 35 fM/mg protein for asthmatic subjects (p < 0.05). A highly statistically significant positive correlation between specific DHA binding (at 12 nM DHA) and FEV1 FVC% was observed (r = 0.93, p < 0.01), with those asthmatic subjects with the more severe airway obstruction and disease severity showing lower DHA binding. The results of the study suggest that a lymphocyte beta adrenergic receptor defect may be present among some patients with asthma. The magnitude of the receptor abnormality appears to be related to disease severity and degree of airway obstruction as measured by FEV1 FVC%. Documentation of drug consumption was made, and restriction of beta adrenergic agonists was attempted; theophylline and corticosteroids were the predominant drugs used in the study. Even with these precautions, it is possible that the differences in DHA binding observed among subjects are the results of greater drug (e.g., theophylline and corticosteroids) consumption by the clinically more severe patients. On the other hand, the lymphocyte receptor alteration noted may reflect a more general beta adrenergic receptor abnormality in bronchial asthma. © 1979.