The ideal treatment of acute fractures of the humeral shaft remains controversial. Recently, tendency of surgical treatment has been increased. Authors reviewed and analyzed plate fixation in 40 patients and intramedullary nailing in 26 patients having humeral shaft fractures. These patients were treated at the department of orthopaedic surgery, Chonju Presbyterian Medical Center from June 1994 to November 1997. There is no significant difference in union time, operation time, functional result. But, non-union rate of intramedullary nailing is superior to that of plate fixation. So, We concluded that plate fixation in humerus shaft fracture is more acceptable than intramedullary nailing, except severe osteoporosis, severe communited fracture, segmental fracture, pathologic fracture.