We experienced a case of giant cell tumor arising from the right 2nd rib in the diagnostic and therapeutic thoracotomy at our department of Thoracic and Cardiovascular Surgery, Chungnam Univ. Hospital in May 3rd, 1991. The reports of this tumor are very rare and are known to have the incidence of 1 percent or less of all giant cell bone tumor. The tumor of the right 2nd rib, infant head-sized, covered with parietal pleura was invaded into the vertebra on operation finding. The tumor was resected partially[three fourths] and revealed to be the giant cell tumor on pathologic finding. At now, the patient is taking the radiotherapy to achieve the therapeutic goal to the remnant tumor.