Background: Neglected non-united lateral humeral condyle fractures in pediatrics are a probable cause of cubitus valgus deformity which is a disabling complication. The ideal management for this condition is still debatable. This study aimed to evaluate the reconstruction of a non-united lateral humerus condylar fracture complicated by cubitus valgus using a tricortical iliac crest graft in pediatric patients. Patients and methods: Twenty children suffering from cubitus valgus as a complication after a non-united fracture of the lateral humeral condyle were included in this study. They were managed by open reduction, screw fixation, and reconstruction by an autologous tricortical iliac bone graft. We compared the preoperative and postoperative range of motion of the elbow, alignment, and elbow function using the Mayo elbow performance index. Results: There was a statistically significant improvement in the elbow range of motion postoperatively, and there was a highly significant improvement regarding the elbow alignment and function. Conclusion: Open reduction, screw fixation, and reconstruction by the autologous tricortical iliac bone graft is an effective technique for the management of cubitus valgus due to neglected non-united lateral humeral condyle fractures in pediatrics.