Background: For adolescents of severely displaced proximal humeral fracture (PHF), surgery is a good choice yielding excellent outcomes. Kirchner wire (KW) is a cost-effective choice for fixation, and this study aims to compare the clinical outcomes of external fixator (EF) vs. KW for the treatment of PHF in adolescents. To the best of our knowledge, it is the first report on external fixator for PHF in children and adolescents.Methods: Patients of PHF operated in our institute, from January 2008 to January 2016, were reviewed retrospectively. Demographic data, including sex, age at the time of surgery, operated side, and hardware choice, were collected from the hospital database. Preoperative radiographs were reviewed and classified according to Neer-Horwitz classification. Shoulder function was evaluated during 12th month follow-up using rating scale of the American shoulder and elbow surgeons (ASES). Complications, including infection, malunion, nonunion, stiffness of the shoulder joint, and failure of fixation were also recorded.Results: Thirty-five patients, including 23 males and 12 females, were included in the EF group, whereas 40 patients, including 25 males and 15 females, were included in the KW group (P = 0.867). The average age of patients in the EF group was 13.3 ± 1.7 years, and that of KW was 13.6 ± 1.8 years (P = 0.409). Patients in both groups were followed-up for at least 12 months. The operative time in the EF group (42.4 ± 11.2, min) was significantly shorter than those in the KW group (54 ± 13.6, min), P < 0.001. The frequency of fluoroscopy in the EF group (12 ± 2.4) was significantly less than those in the KW group (17 ± 2.8), P < 0.001. The rate of open reduction was significantly higher in KW (35%) group than those in the EF group (0%), P < 0.001. There was no nonunion, malunion cases in both groups.Conclusion: External fixator is superior to Kirschner wire in the treatment of proximal humeral fractures in adolescents with shorter operative time, lower rate of ORIF and comparable clinical outcomes.