Four cases of pulmonary Nocardia infection were reported and the 22 cases reported in our country between 1980 and 1993 were analyzed together for the purpose of revealing the clinical picture of this disease in China. There was approximately a ratio of two male patients to one female (18:8) with a mean age of 40 years in this series of patients. Various underlying diseases were found as predisposing factors in 69% (18/26) of the cases. 34.5% (9/26) of the cases had a history of corticosteroid therapy. Pleural effusion was identified in 50% (13/26) of the patients. 38% (10/26) of the patients died. Patients with primary pulmonary Nocardia infection had a better prognosis than those with secondary infection. Appropriate culture media, sufficient culture time and repeated cultures were recommended to improve the positive identification rate of this special causative agent. The sulfonamides were the drugs of first choice along with prompt drainage of thoracic empyema and abscess.