In order to inquire into the functional state of adrenal cortex in patients with pulmonary heart disease, the number of glucocorticoid receptors(GCR) of peripheral blood leukocytes in patients with chronic pulmonary heart disease was determined with radioligand-binding assay and the corresponding plasma cortisol levels were assessed with radioimmune assays. The results showed that the number of GCR in the patients was significantly reduced (P < 0.01) and it was increased when their health state was improved. However, it was still lower than that in healthy subjects (P < 0.01). The number of GCR in the patients was greatly increased when these patients were treated with oxygen (P < 0.01). No difference in plasma cortisol was found between the patients and the healthy subjects (P > 0.05). These results indicate that the function of adrenal cortex may be improved by the compensation mechanism of the patients, but the lower GCR number was the result of lacking of oxygen in the patients. The number of GCR may be improved by inhalation of oxygen. Therefore oxygen therapy is helpful in raising the activity of glucocorticoid receptors and controlling the development of the disease.