Pancoast tumor was specific lung carcinoma that has been symptoms and signs according to locations. It was located in peripheral,and involved the extrathoracic structures more than parenchyme of the lung. At 1838, Hare reported it, and at 1932 Pancoast was first described it. Prior to 1950,superior sulcus tumor was considered uniformly fatal, but at 1961 Paulson and Shaw advocated the use of preoperative irradiation therapy and followed by an extended en bloc resection. Recently we were experienced 2 cases of pancoast tumor managed with same method. One was 60-years old man that has been recommended preoperative radiation therapy with dose of 3000 cGy to 20 fractions and followed resection after 4 weeks, the other was 53-years old man that has been recommended a dose of 4000 cGy to 20 fractions and followed resection after 4 weeks. On tumor histology first case was large cell carcinoma and second case was squamous cell carcinoma. all patients was complicated atelectasis. First patient was expired with brain metastasis after 17 months, second was expired after 6 months.