In 1814, Monteggia first described a fracture of proximal third of the ulna with a dislocation of radial head. The clinical importance of this fracture is that when the ulna is fractured and shortened, the proximal radioulnar joint dislocate. Despite of its importance the reports of this fracture is relatively rare. The authors reviewed twenty-nine Monteggia fractures that were treated at 15 orthopedic institutes of Honam area over a four-year period (1981 through 1984), with particular emphasis on classification, causes of injury, level of fracture, direction of dislocation, treatment and results. The results were as follows: 1. Total 29 patients were 8 children and 21 adults. 2. The male was affected about 2 times more than female (19: 10). 3. Causes of injury were fall in 12, car accident in 12 and machinery injury in 5. 4. Classification into 4 type by Bado's method disclosed that type 1 accounts for 65.5% of cases, type 2 for 6.9%,type 3 for 13.8%, and type 4 for 13.8%. 5. Treatments of dislocated radial head were closed reduction in 24, open reduction in 3, and excision in 2. 6. Locational incidence of ulnar fracture were upper one third of ulna in 11, junction of upper and middle 1/3 in 2, middle one third in 15, and distal one third in 1. 7. Treatment of fractured ulna was different between child and adult. Eight children fracture were managed by closed reduction in 5 and open reduction with K-wire fixation in 3. Twenty one adult fracture were managed by open reduction and internal fixation in 20 and closed reduction in l. 8. Palsy of posterior interosseous nerve was observed in 3 patients (10.4%) and disappeared completely later. 9. The results (Bruce et al criteria) for the 19 patients followed 6 months and more were 8 excellent, 4 good, 1 fair and 1 poor.