Purpose: This retrospective study aims to evaluate the results of management of residual acetabular dysplasia using Dega osteotomy after open reduction of developmental dysplasia of the hip. Patients & Methods: Twenty-three hips in twenty patients (17 girls and three boys) with residual acetabular dysplasia after open reduction of developmental dysplasia of the hip underwent Dega acetabuloplasty with or without plate femur extraction. There were 17 unilateral and 3 bilateral DDH, regarding the unilateral cases; nine cases were left-sided DDH and eight cases were right-sided DDH. Results: Results of treatment were evaluated radiologically using the acetabular index, central edge angle and development of the acetabular sourcil. All hips at the final follow-up showed well remodeled acetabulum with normalization of all radiological parameters. Conclusion Dega osteotomy is an effective tool for treatment of residual acetabular dysplasia to prevent its expected degenerative hip changes.