A 32-year-old housewife with AT III abnormality visited our out-patient clinic because of dyspnea on April 14, 1988, and was diagnosed as bronchial asthma of non-atopic type. In spite of treatment, her asthmatic symptom did not improve. Therefore, she was admitted to our department on August 12 for a detailed examination and more effective therapy. Xanthine derivatives and beta 2 stimulant were ineffective, and only steroid hormone was effective to some degree. Pulmonary perfusion scan revealed that her pulmonary thromboembolism had become worse. Then she was treated with AT III concentrate and urokinase and her asthmatic symptom was significantly improved and steroid hormone could be easily reduced. Her asthmatic symptom was suggested to be due to progression of pulmonary thromboembolism. We were not able to find any other report of a case with AT III abnormality presenting as bronchial asthma due to pulmonary thromboembolism.