Objective: This study aimed to compare the outcomes of medial, lateral, posterior, and anterior approaches in pediatric Gartland type 3 supracondylar humerus fractures treated with open reduction and pinning. Methods: Gartland type 3 supracondylar humeral fractures treated by open reduction and pinning in 4 different centers with different surgical approaches were divided into 4 groups according to the surgical approach. Each trauma center applied the surgical approaches with which it had the most experience. Specifically, patients treated with medial, lateral, posterior, and anterior approaches were classified as groups 1, 2, 3, and 4, respectively. The demographic characteristics of the patients and the complications were compared. The findings were evaluated according to the Flynn criteria. Results: A total of 198 pediatric patients, 114 (57.6%) male and 84 (42.4%) female, with a mean age of 6.27 ± 2.03 (range = 1-12) years, were included in this study. They were all treated with open reduction and pinning, 51 (25.8%) by the medial approach, 49 (24.7%) by the lateral approach, 66 (33.3%) by the posterior approach, and 32 (16.2%) by the anterior approach. No significant differences in age, gender, side, or complication status were found between the groups (P > .05). There were also no significant differences between the groups regarding the Flynn cosmetic and functional criteria (P > .05). Conclusions: Superior functional and cosmetic results can be achieved with fewer complications with surgical techniques applied by experienced surgeons in the open reduction of supracondylar humeral fractures in children. It is recommended that surgeons choose the approach with which they have the most experience.