Objective: To evaluate the effect of Ilizarov mini-fixator in the treatment of fresh Monteggia fractures in children. Methods: A total of 12 children with fresh Monteggia fractures were enrolled in this study, who underwent Ilizarov mini-fixator, intraoperative fracture reduction, arthrography to evaluate the reduction effect, and postoperative forearm plaster fixation in supination position. Results: All patients had surgical procedures performed smoothly without serious complications. All 12 children were followed up for 6-12 months. At the last follow-up, the range of elbow flexion and extension and the forearm rotation were restored well. Compared with 4 weeks after the operation, the range of elbow flexion and extension was significantly increased (P<0.05), and the range of forearm rotation was significantly increased (P< 0.05). According to Mayo Elbow joint scoring criteria and postoperative images, both of the excellent rate of surgery effect and fracture reduction quality was 100%. Compared with 4 weeks after operation, the fractures of all cases were healed at the last follow-up, and the difference was statistically significant (P<0.05). There was no significant difference between control and case group about brachioradial joint alignment and normal ulnar force lines (P>0.05). Conclusion: For fresh children's Monteggia fractures, the fracture types are unstable of proximal ulna, Ilizarov mini-fixator is an effective treatment method, which is simple to operate and less traumatic, and is worthy of promotion.