Purpose: The purpose of this study was to know the usefulness of bony union and faster recovery of shoulder motions by the open reduction and internal fixation with the reconstruction plate for the displaced clavicle shaft fracture of adults. Material and method: From January 1993 to December 1997, for 5 years, we analyzed 28 cases which underwent for a year of displaced clavicular shaft fracture over 11mm after open reduction and internal fixation with the reconstruction plate and supplementary iliac bone graft. Result: At all 28 cases, there were united without delayed union for average 7.2 weeks after operation. Motion of the shoulder joint were returned to normal within 1.8 weeks except two cases who had combined humerus fracture and partial gastrectomy for peptic ulcer. Conclusion: It seems that operative treatment with the reconstruction plate and supplementary bone graft for the displaced clavicle shaft fracture of adults showed effective union and faster recovery of shoulder motions.