Although the clavicle is one of the most commonly fractured bone, nonunion is rare. The authors experienced 15 cases of clavicle nonunion in adult who were admitted and treated at the Department of Orthopedic Surgery of Severance Hospital during period from January 1983 to December 1990 (eight years). This study focused on the predisposing factors in relation to nonunion of clavicle and the analysis of the results after operative treatment The results of analysis wire as follows ; 1. Predisposing factors of nonunion were primary operative treatment with inadequate fixation, middle 1/3 of clavicle, severe associated injury and initial gross displacement of fracture fragment. 2. Among the 15 patients, 14 patients were treated with plate and screw fixation and autogenous iliac bone graft. One patient was treated by metal removal due to infected nonunion. 3. Using a rating scale of excellent(no apparent fractors), good(one factor), fair(two factors), poor(more than three factors), the result showed, 12 excellent, 1 good, and 2 poor 4. Amonf the is opeTative treatment, there was only one case of complication which was metal failure. It was concluded that symptomatic nonunion of the clavicle could be treated by operation. and the procedure of choice seemed to be rigid internal fixation with plate and bone graft.