Abstract: The binding capacity of estrogen receptor (ER) and rogen receptor(AR) in peripheral leucocytes in women with lung cancer was determined by the method of radioligand binding assay and plasma estradiol (E₂) and testosterone (T) levels were simultaneously measured by radioimmune assay in 22 women lung cancer. The results were compared with those of 25 age-matched healthy Women. It was found that the level of plasma estradiol (E₂) was significantly increased in 5 patients with normal menstrual cycle,but not in 17 patients with menopsuse.The level of testosterone was significantly decreased in all the patients. The ratio of E₂ to T was also significantly increased. The result still showed that the content of AR in leucocytes was obviosly lowered and the content of ER and the ratio of ER to AR were obviously elevated. It suggested that the disturbance of E₂ and T and their receptors may play an important role in the pathogenesis of lung cancer in women.